From 0fef360caf43278c6536e08312a1a0f876581674 Mon Sep 17 00:00:00 2001
From: "S. Mahmudul Hasan" <mahmudulhasan947@gmail.com>
Date: Tue, 3 Oct 2023 13:45:21 -0400
Subject: [PATCH 01/28] Added better string formatting as required by Issue#138

---
 python/builtins.py | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/python/builtins.py b/python/builtins.py
index 4abb8187..19193a58 100644
--- a/python/builtins.py
+++ b/python/builtins.py
@@ -96,13 +96,20 @@ def sorted(iterable, reverse=False, key=None):
     return a
 
 ##### str #####
-def __f(self, *args):
+def __f(self, *args, **kwargs):
     if '{}' in self:
         for i in range(len(args)):
             self = self.replace('{}', str(args[i]), 1)
     else:
-        for i in range(len(args)):
-            self = self.replace('{'+str(i)+'}', str(args[i]))
+        # Positional arguments will be followed by keyword arguments
+        # 1. Replace the positional arguments
+        for i,a in enumerate(args):
+            self = self.replace('{'+str(i)+'}', str(a))
+        
+        # 2. Replace the keyword arguments
+        for k,v in kwargs.items():
+            self = self.replace('{'+k+'}', str(v))
+    
     return self
 str.format = __f
 

From c18821fc42f056378174c70017ab68b8c2558b99 Mon Sep 17 00:00:00 2001
From: Non <43197300+nonperforming@users.noreply.github.com>
Date: Thu, 5 Oct 2023 19:16:40 +1300
Subject: [PATCH 02/28] Powershell-ify build.ps1

Convert *nix commands to PowerShell commands
---
 build.ps1 | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/build.ps1 b/build.ps1
index 3b794a76..af980cfe 100644
--- a/build.ps1
+++ b/build.ps1
@@ -1,9 +1,12 @@
 if (Test-Path build) {
     Remove-Item -Recurse -Force build
 }
-mkdir build
-cd build
+
+New-Item -ItemType Directory -Path build
+Push-Location build
+
 cmake ..
 cmake --build . --config Release
-cp Release/main.exe ../
-cp Release/pocketpy.dll ../
\ No newline at end of file
+
+Copy-Item "Release\main.exe" -Destination ".." # Note: NTFS uses backslash (\) instead of slashes (*nix, /) 
+Copy-Item "Release\pocketpy.dll" -Destination ".."

From 63bf13aac245b2b68f4238e89b865364f3841997 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Fri, 6 Oct 2023 00:58:08 +0800
Subject: [PATCH 03/28] some minor change

---
 build.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build.sh b/build.sh
index 00290fe2..ff84b5dc 100644
--- a/build.sh
+++ b/build.sh
@@ -45,7 +45,7 @@ echo "> Compiling main.cpp and linking to libpocketpy$LIB_EXTENSION..."
 clang++ $FLAGS -o main src2/main.cpp -L. -lpocketpy $LINK_FLAGS
 
 if [ $? -eq 0 ]; then
-    echo "Build completed successfully. To use pocketpy, run : ./main"
+    echo "Build completed. Type \"./main\" to enter REPL."
 else
     echo "Build failed."
     exit 1

From 52c58ec87f44789a76b374bddb19a98b589f0db5 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Fri, 6 Oct 2023 01:13:19 +0800
Subject: [PATCH 04/28] Update 70_math.py

---
 tests/70_math.py | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/tests/70_math.py b/tests/70_math.py
index 0545aabc..4dbcce67 100644
--- a/tests/70_math.py
+++ b/tests/70_math.py
@@ -25,4 +25,34 @@ assert floor(-1.2) == -2
 assert ceil(1.2) == 2
 assert ceil(-1.2) == -1
 
-assert isclose(sqrt(4), 2.0)
\ No newline at end of file
+assert isclose(sqrt(4), 2.0)
+
+import math
+
+# test fsum
+assert math.fsum([0.1] * 10) == 1.0
+
+# test gcd
+assert math.gcd(10, 5) == 5
+assert math.gcd(10, 6) == 2
+assert math.gcd(10, 7) == 1
+assert math.gcd(10, 10) == 10
+assert math.gcd(-10, 10) == 10
+
+# test modf
+x, y = math.modf(1.5)
+assert isclose(x, 0.5)
+assert isclose(y, 1.0)
+
+x, y = math.modf(-1.5)
+assert isclose(x, -0.5)
+assert isclose(y, -1.0)
+
+# test factorial
+assert math.factorial(0) == 1
+assert math.factorial(1) == 1
+assert math.factorial(2) == 2
+assert math.factorial(3) == 6
+assert math.factorial(4) == 24
+assert math.factorial(5) == 120
+

From 5b42930ede1612af217e5ec52f98185b554d9172 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Fri, 6 Oct 2023 01:25:22 +0800
Subject: [PATCH 05/28] ...

---
 CMakeLists.txt | 6 +++---
 build.sh       | 6 ++----
 2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7f05b5b5..1587d222 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,13 +27,13 @@ endif()
 
 if(EMSCRIPTEN)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
-    set(CMAKE_CXX_FLAGS_RELEASE "-O3")
+    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
 elseif(MSVC)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc /utf-8")
-    set(CMAKE_CXX_FLAGS_RELEASE "/O2")
+    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /O2")
 else()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
-    set(CMAKE_CXX_FLAGS_RELEASE "-O2")
+    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2")
 endif()
 
 include_directories(${CMAKE_CURRENT_LIST_DIR}/include)
diff --git a/build.sh b/build.sh
index ff84b5dc..473b1f7d 100644
--- a/build.sh
+++ b/build.sh
@@ -21,13 +21,11 @@ echo "> Running prebuild.py... "
 
 python3 prebuild.py
 
-# echo -n "Finding source files... "
 SRC=$(find src/ -name "*.cpp")
-# echo "Done"
 
 echo "> Compiling and linking source files... "
 
-FLAGS="-std=c++17 -O2 -stdlib=libc++ -Wfatal-errors -Iinclude"
+FLAGS="-std=c++17 -O1 -stdlib=libc++ -Wfatal-errors -Iinclude"
 if [[ "$OSTYPE" == "darwin"* ]]; then
     LIB_EXTENSION=".dylib"
     FLAGS="$FLAGS -undefined dynamic_lookup"
@@ -42,7 +40,7 @@ clang++ $FLAGS -o libpocketpy$LIB_EXTENSION $SRC -fPIC -shared -ldl
 # compile main.cpp and link to libpocketpy.so
 echo "> Compiling main.cpp and linking to libpocketpy$LIB_EXTENSION..."
 
-clang++ $FLAGS -o main src2/main.cpp -L. -lpocketpy $LINK_FLAGS
+clang++ $FLAGS -o main -O1 src2/main.cpp -L. -lpocketpy $LINK_FLAGS
 
 if [ $? -eq 0 ]; then
     echo "Build completed. Type \"./main\" to enter REPL."

From 59b1c13f354b7b819a16b2f94b9bda8b428fd710 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Fri, 6 Oct 2023 01:30:20 +0800
Subject: [PATCH 06/28] Update CMakeLists.txt

---
 CMakeLists.txt | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1587d222..67a0e8a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,19 +21,12 @@ if(NOT ${PREBUILD_RESULT} EQUAL 0)
     message(FATAL_ERROR "prebuild.py: ${PREBUILD_RESULT}")
 endif()
 
-if(MSVC)
-    add_compile_options("/utf-8")
-endif()
-
 if(EMSCRIPTEN)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
-    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions -O3")
 elseif(MSVC)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc /utf-8")
-    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /O2")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc /utf-8 /O2")
 else()
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
-    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions -O2")
 endif()
 
 include_directories(${CMAKE_CURRENT_LIST_DIR}/include)

From ee548164218d0f1c22759d6d6cd7ca5e42f297b8 Mon Sep 17 00:00:00 2001
From: "S. Mahmudul Hasan" <mahmudulhasan947@gmail.com>
Date: Thu, 5 Oct 2023 20:04:21 -0400
Subject: [PATCH 07/28] Updated str.format to tokenization-based-replacement
 operation

---
 python/builtins.py | 119 +++++++++++++++++++++++++++++++++++++++------
 1 file changed, 105 insertions(+), 14 deletions(-)

diff --git a/python/builtins.py b/python/builtins.py
index 19193a58..1f096cc1 100644
--- a/python/builtins.py
+++ b/python/builtins.py
@@ -96,21 +96,112 @@ def sorted(iterable, reverse=False, key=None):
     return a
 
 ##### str #####
-def __f(self, *args, **kwargs):
-    if '{}' in self:
-        for i in range(len(args)):
-            self = self.replace('{}', str(args[i]), 1)
-    else:
-        # Positional arguments will be followed by keyword arguments
-        # 1. Replace the positional arguments
-        for i,a in enumerate(args):
-            self = self.replace('{'+str(i)+'}', str(a))
-        
-        # 2. Replace the keyword arguments
-        for k,v in kwargs.items():
-            self = self.replace('{'+k+'}', str(v))
+def tokenize(s:str) -> list:
+    tokens = []
+    L, R = 0,0
     
-    return self
+    mode = None
+    curPos = 0
+    lookingForKword = False
+    
+    while(R<len(s) and not lookingForKword):
+        curChar = s[R]
+        nextChar = s[R+1] if R+1<len(s) else ''
+        
+        # Escaping case
+        if (curChar == '{' and nextChar == '{') or (curChar == '}' and nextChar == '}'):
+            tokens.append(curChar)
+            L = R+2
+            R = R+2
+            continue
+        
+        # Regular command line arg case
+        if curChar == '{' and nextChar == '}':
+            
+            if mode is not None and mode != 'auto':
+                raise ValueError("Cannot switch from manual field numbering to automatic field specification")
+            
+            mode = 'auto'
+            # best case {}, just for normal args
+            if(L<R):
+                tokens.append(s[L:R])
+            tokens.append("{"+str(curPos)+"}")
+            curPos+=1
+            L = R+2
+            R = R+2
+            continue
+        
+        # Kwarg case
+        elif (curChar == '{'):
+            
+            if mode is not None and mode != 'manual':
+                raise ValueError("Cannot switch from automatic field specification to manual field numbering")
+            
+            mode = 'manual'
+            
+            if(L<R):
+                tokens.append(s[L:R])
+            
+            lookingForKword = True
+            kwL = R+1
+            kwR = R+1
+            while(kwR<len(s) and s[kwR]!='}'):
+                kwR += 1
+            tokens.append(s[R:kwR+1])
+            
+            if kwR<len(s) and s[kwR] == '}':
+                lookingForKword = False
+                L = kwR+1
+                R = kwR+1
+            continue
+        
+        R = R+1
+    
+    if lookingForKword:
+        raise ValueError("Expected '}' before end of string")
+    
+    if(not lookingForKword and L<R):
+        tokens.append(s[L:R])
+
+    # print("Looking for kword: ", lookingForKword)
+    return tokens
+def __f(self:str, *args, **kwargs) -> str:
+    tokens = tokenize(self)
+    argMap = {}
+    for i, a in enumerate(args):
+        argMap[str(i)] = a
+    final_tokens = []
+    for t in tokens:
+        if t[0] == '{' and t[-1] == '}':
+            key = t[1:-1]
+            argMapVal = argMap.get(key, None)
+            kwargsVal = kwargs.get(key, None)
+            
+            if argMapVal is None and kwargsVal is None:
+                raise ValueError("No arg found for token: "+t)
+            elif argMapVal is not None:
+                final_tokens.append(str(argMapVal))
+            else:
+                final_tokens.append(str(kwargsVal))
+        else:
+            final_tokens.append(t)
+    
+    return ''.join(final_tokens)
+ 
+    # if '{}' in self:
+    #     for i in range(len(args)):
+    #         self = self.replace('{}', str(args[i]), 1)
+    # else:
+    #     # Positional arguments will be followed by keyword arguments
+    #     # 1. Replace the positional arguments
+    #     for i,a in enumerate(args):
+    #         self = self.replace('{'+str(i)+'}', str(a))
+        
+    #     # 2. Replace the keyword arguments
+    #     for k,v in kwargs.items():
+    #         self = self.replace('{'+k+'}', str(v))
+    
+    # return self
 str.format = __f
 
 def __f(self, chars=None):

From 151e9467ae717c0dd9acc4fcfb5adbe24fed3279 Mon Sep 17 00:00:00 2001
From: "S. Mahmudul Hasan" <mahmudulhasan947@gmail.com>
Date: Fri, 6 Oct 2023 16:56:19 -0400
Subject: [PATCH 08/28] fixed the error case for escaped curly braces, and
 converted the tokenize function into a inner function

---
 python/builtins.py | 161 +++++++++++++++++++++++++--------------------
 1 file changed, 89 insertions(+), 72 deletions(-)

diff --git a/python/builtins.py b/python/builtins.py
index 1f096cc1..9528160b 100644
--- a/python/builtins.py
+++ b/python/builtins.py
@@ -96,77 +96,94 @@ def sorted(iterable, reverse=False, key=None):
     return a
 
 ##### str #####
-def tokenize(s:str) -> list:
-    tokens = []
-    L, R = 0,0
-    
-    mode = None
-    curPos = 0
-    lookingForKword = False
-    
-    while(R<len(s) and not lookingForKword):
-        curChar = s[R]
-        nextChar = s[R+1] if R+1<len(s) else ''
-        
-        # Escaping case
-        if (curChar == '{' and nextChar == '{') or (curChar == '}' and nextChar == '}'):
-            tokens.append(curChar)
-            L = R+2
-            R = R+2
-            continue
-        
-        # Regular command line arg case
-        if curChar == '{' and nextChar == '}':
-            
-            if mode is not None and mode != 'auto':
-                raise ValueError("Cannot switch from manual field numbering to automatic field specification")
-            
-            mode = 'auto'
-            # best case {}, just for normal args
-            if(L<R):
-                tokens.append(s[L:R])
-            tokens.append("{"+str(curPos)+"}")
-            curPos+=1
-            L = R+2
-            R = R+2
-            continue
-        
-        # Kwarg case
-        elif (curChar == '{'):
-            
-            if mode is not None and mode != 'manual':
-                raise ValueError("Cannot switch from automatic field specification to manual field numbering")
-            
-            mode = 'manual'
-            
-            if(L<R):
-                tokens.append(s[L:R])
-            
-            lookingForKword = True
-            kwL = R+1
-            kwR = R+1
-            while(kwR<len(s) and s[kwR]!='}'):
-                kwR += 1
-            tokens.append(s[R:kwR+1])
-            
-            if kwR<len(s) and s[kwR] == '}':
-                lookingForKword = False
-                L = kwR+1
-                R = kwR+1
-            continue
-        
-        R = R+1
-    
-    if lookingForKword:
-        raise ValueError("Expected '}' before end of string")
-    
-    if(not lookingForKword and L<R):
-        tokens.append(s[L:R])
-
-    # print("Looking for kword: ", lookingForKword)
-    return tokens
 def __f(self:str, *args, **kwargs) -> str:
-    tokens = tokenize(self)
+    def tokenizeString(s:str):
+        tokens = []
+        L, R = 0,0
+        
+        mode = None
+        curArg = 0
+        # lookingForKword = False
+        
+        while(R<len(s)):
+            curChar = s[R]
+            nextChar = s[R+1] if R+1<len(s) else ''
+            
+            # Invalid case 1: stray '}' encountered, example: "ABCD EFGH {name} IJKL}", "Hello {vv}}", "HELLO {0} WORLD}"
+            if curChar == '}' and nextChar != '}':
+                raise ValueError("Single '}' encountered in format string")        
+            
+            # Valid Case 1: Escaping case, we escape "{{ or "}}" to be "{" or "}", example: "{{}}", "{{My Name is {0}}}"
+            if (curChar == '{' and nextChar == '{') or (curChar == '}' and nextChar == '}'):
+                
+                if (L<R): # Valid Case 1.1: make sure we are not adding empty string
+                    tokens.append(s[L:R]) # add the string before the escape
+                
+                
+                tokens.append(curChar) # Valid Case 1.2: add the escape char
+                L = R+2 # move the left pointer to the next char
+                R = R+2 # move the right pointer to the next char
+                continue
+            
+            # Valid Case 2: Regular command line arg case: example:  "ABCD EFGH {} IJKL", "{}", "HELLO {} WORLD"
+            elif curChar == '{' and nextChar == '}':
+                if mode is not None and mode != 'auto':
+                    # Invalid case 2: mixing automatic and manual field specifications -- example: "ABCD EFGH {name} IJKL {}", "Hello {vv} {}", "HELLO {0} WORLD {}" 
+                    raise ValueError("Cannot switch from manual field numbering to automatic field specification")
+                
+                mode = 'auto'
+                if(L<R): # Valid Case 2.1: make sure we are not adding empty string
+                    tokens.append(s[L:R]) # add the string before the special marker for the arg
+                
+                tokens.append("{"+str(curArg)+"}") # Valid Case 2.2: add the special marker for the arg
+                curArg+=1 # increment the arg position, this will be used for referencing the arg later
+                
+                L = R+2 # move the left pointer to the next char
+                R = R+2 # move the right pointer to the next char
+                continue
+            
+            # Valid Case 3: Key-word arg case: example: "ABCD EFGH {name} IJKL", "Hello {vv}", "HELLO {name} WORLD"
+            elif (curChar == '{'):
+                
+                if mode is not None and mode != 'manual':
+                    # # Invalid case 2: mixing automatic and manual field specifications -- example: "ABCD EFGH {} IJKL {name}", "Hello {} {1}", "HELLO {} WORLD {name}"
+                    raise ValueError("Cannot switch from automatic field specification to manual field numbering")
+                
+                mode = 'manual'
+                
+                if(L<R): # Valid case 3.1: make sure we are not adding empty string
+                    tokens.append(s[L:R]) # add the string before the special marker for the arg
+                
+                # We look for the end of the keyword          
+                kwL = R # Keyword left pointer
+                kwR = R+1 # Keyword right pointer
+                while(kwR<len(s) and s[kwR]!='}'):
+                    if s[kwR] == '{': # Invalid case 3: stray '{' encountered, example: "ABCD EFGH {n{ame} IJKL {", "Hello {vv{}}", "HELLO {0} WOR{LD}"
+                        raise ValueError("Unexpected '{' in field name")
+                    kwR += 1
+                
+                # Valid case 3.2: We have successfully found the end of the keyword
+                if kwR<len(s) and s[kwR] == '}':
+                    tokens.append(s[kwL:kwR+1]) # add the special marker for the arg
+                    L = kwR+1
+                    R = kwR+1
+                    
+                # Invalid case 4: We didn't find the end of the keyword, throw error
+                else:
+                    raise ValueError("Expected '}' before end of string")
+                continue
+            
+            R = R+1
+        
+        
+        # Valid case 4: We have reached the end of the string, add the remaining string to the tokens 
+        if L<R:
+            tokens.append(s[L:R])
+                
+        # print(tokens)
+        return tokens
+
+    tokens = tokenizeString(self)
     argMap = {}
     for i, a in enumerate(args):
         argMap[str(i)] = a
@@ -176,7 +193,7 @@ def __f(self:str, *args, **kwargs) -> str:
             key = t[1:-1]
             argMapVal = argMap.get(key, None)
             kwargsVal = kwargs.get(key, None)
-            
+                                    
             if argMapVal is None and kwargsVal is None:
                 raise ValueError("No arg found for token: "+t)
             elif argMapVal is not None:
@@ -187,7 +204,7 @@ def __f(self:str, *args, **kwargs) -> str:
             final_tokens.append(t)
     
     return ''.join(final_tokens)
- 
+
     # if '{}' in self:
     #     for i in range(len(args)):
     #         self = self.replace('{}', str(args[i]), 1)

From 2f525617090d57274c7fcf615f5ea76938d7444e Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sat, 7 Oct 2023 11:37:36 +0800
Subject: [PATCH 09/28] add more json test cases

---
 tests/80_json.py | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/tests/80_json.py b/tests/80_json.py
index d821ab92..1e0f1ccc 100644
--- a/tests/80_json.py
+++ b/tests/80_json.py
@@ -16,6 +16,15 @@ a = {
 
 import json
 
+assert json.loads("1") == 1
+assert json.loads('"1"') == "1"
+assert json.loads("0.0") == 0.0
+assert json.loads("[1, 2]") == [1, 2]
+assert json.loads("null") == None
+assert json.loads("true") == True
+assert json.loads("false") == False
+assert json.loads("{}") == {}
+
 _j = json.dumps(a)
 _a = json.loads(_j)
 

From 098b85f89b90dfbd15e24fbc83dc181951d58263 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sat, 7 Oct 2023 11:55:57 +0800
Subject: [PATCH 10/28] ...

---
 python/builtins.py | 18 ++----------------
 tests/04_str.py    | 13 +++++++++++++
 2 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/python/builtins.py b/python/builtins.py
index 9528160b..436cd39c 100644
--- a/python/builtins.py
+++ b/python/builtins.py
@@ -96,8 +96,8 @@ def sorted(iterable, reverse=False, key=None):
     return a
 
 ##### str #####
-def __f(self:str, *args, **kwargs) -> str:
-    def tokenizeString(s:str):
+def __f(self: str, *args, **kwargs) -> str:
+    def tokenizeString(s: str):
         tokens = []
         L, R = 0,0
         
@@ -205,20 +205,6 @@ def __f(self:str, *args, **kwargs) -> str:
     
     return ''.join(final_tokens)
 
-    # if '{}' in self:
-    #     for i in range(len(args)):
-    #         self = self.replace('{}', str(args[i]), 1)
-    # else:
-    #     # Positional arguments will be followed by keyword arguments
-    #     # 1. Replace the positional arguments
-    #     for i,a in enumerate(args):
-    #         self = self.replace('{'+str(i)+'}', str(a))
-        
-    #     # 2. Replace the keyword arguments
-    #     for k,v in kwargs.items():
-    #         self = self.replace('{'+k+'}', str(v))
-    
-    # return self
 str.format = __f
 
 def __f(self, chars=None):
diff --git a/tests/04_str.py b/tests/04_str.py
index dd4a1587..6a2e1a44 100644
--- a/tests/04_str.py
+++ b/tests/04_str.py
@@ -97,6 +97,19 @@ assert "{0} {1} {2}".format("I", "love", "Python") == "I love Python"
 assert "{2} {1} {0}".format("I", "love", "Python") == "Python love I"
 assert "{0}{1}{0}".format("abra", "cad") == "abracadabra"
 
+assert "{k}={v}".format(k="key", v="value") == "key=value"
+assert "{k}={k}".format(k="key") == "key=key"
+assert "{0}={1}".format('{0}', '{1}') == "{0}={1}"
+assert "{{{0}}}".format(1) == "{1}"
+assert "{0}{1}{1}".format(1, 2, 3) == "122"
+try:
+    "{0}={1}}".format(1, 2)
+    exit(1)
+except ValueError:
+    pass
+assert "{{{}xxx{}x}}".format(1, 2) == "{1xxx2x}"
+assert "{{abc}}".format() == "{abc}"
+
 # 3rd slice
 a = "Hello, World!"
 assert a[::-1] == "!dlroW ,olleH"

From 7312afdad24bb308037088d34b32ed0078fed7d2 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sat, 7 Oct 2023 13:28:20 +0800
Subject: [PATCH 11/28] fix a term

---
 README.md     | 2 +-
 README_zh.md  | 2 +-
 docs/index.md | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index f0063c8d..18095dd3 100644
--- a/README.md
+++ b/README.md
@@ -38,7 +38,7 @@ These platforms are officially tested.
 + Android 64-bit / 32-bit
 + iOS 64-bit
 + Emscripten 32-bit
-+ Raspberry Pi 64-bit
++ Raspberry Pi OS 64-bit
 
 ## Quick Start
 
diff --git a/README_zh.md b/README_zh.md
index 9e1394b8..7a6f33b6 100644
--- a/README_zh.md
+++ b/README_zh.md
@@ -27,7 +27,7 @@ pkpy 支持任何拥有 C++17 编译器的平台。
 + Android 64-bit / 32-bit
 + iOS 64-bit
 + Emscripten 32-bit
-+ Raspberry Pi 64-bit
++ Raspberry Pi OS 64-bit
 
 ## 快速上手
 
diff --git a/docs/index.md b/docs/index.md
index 673dc2ee..08ed87c3 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -39,7 +39,7 @@ These platforms are officially tested.
 + Android 64-bit / 32-bit
 + iOS 64-bit
 + Emscripten 32-bit
-+ Raspberry Pi 64-bit
++ Raspberry Pi OS 64-bit
 
 ## Sponsor me
 

From b29801bbe8dc03ceca3475a828dd6143585b8887 Mon Sep 17 00:00:00 2001
From: Non <43197300+nonperforming@users.noreply.github.com>
Date: Sun, 8 Oct 2023 00:11:20 +1300
Subject: [PATCH 12/28] Use emojis in feature list

---
 README.md | 40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index 18095dd3..027bd9ed 100644
--- a/README.md
+++ b/README.md
@@ -114,26 +114,26 @@ for a quick overview of the supported features.
 
 | Name            | Example                         | Supported |
 | --------------- | ------------------------------- | --------- |
-| If Else         | `if..else..elif`                | YES       |
-| Loop            | `for/while/break/continue`      | YES       |
-| Function        | `def f(x,*args,y=1):`           | YES       |
-| Subclass        | `class A(B):`                   | YES       |
-| List            | `[1, 2, 'a']`                   | YES       |
-| ListComp        | `[i for i in range(5)]`         | YES       |
-| Slice           | `a[1:2], a[:2], a[1:]`          | YES       |
-| Tuple           | `(1, 2, 'a')`                   | YES       |
-| Dict            | `{'a': 1, 'b': 2}`              | YES       |
-| F-String        | `f'value is {x}'`               | YES       |
-| Unpacking       | `a, b = 1, 2`                   | YES       |
-| Star Unpacking  | `a, *b = [1, 2, 3]`             | YES       |
-| Exception       | `raise/try..catch`              | YES       |
-| Dynamic Code    | `eval()/exec()`                 | YES       |
-| Reflection      | `hasattr()/getattr()/setattr()` | YES       |
-| Import          | `import/from..import`           | YES       |
-| Context Block   | `with <expr> as <id>:`          | YES       |
-| Type Annotation | `def  f(a:int, b:float=1)`      | YES       |
-| Generator       | `yield i`                       | YES       |
-| Decorator       | `@cache`                        | YES       |
+| If Else         | `if..else..elif`                | ✅       |
+| Loop            | `for/while/break/continue`      | ✅       |
+| Function        | `def f(x,*args,y=1):`           | ✅       |
+| Subclass        | `class A(B):`                   | ✅       |
+| List            | `[1, 2, 'a']`                   | ✅       |
+| ListComp        | `[i for i in range(5)]`         | ✅       |
+| Slice           | `a[1:2], a[:2], a[1:]`          | ✅       |
+| Tuple           | `(1, 2, 'a')`                   | ✅       |
+| Dict            | `{'a': 1, 'b': 2}`              | ✅       |
+| F-String        | `f'value is {x}'`               | ✅       |
+| Unpacking       | `a, b = 1, 2`                   | ✅       |
+| Star Unpacking  | `a, *b = [1, 2, 3]`             | ✅       |
+| Exception       | `raise/try..catch`              | ✅       |
+| Dynamic Code    | `eval()/exec()`                 | ✅       |
+| Reflection      | `hasattr()/getattr()/setattr()` | ✅       |
+| Import          | `import/from..import`           | ✅       |
+| Context Block   | `with <expr> as <id>:`          | ✅       |
+| Type Annotation | `def  f(a:int, b:float=1)`      | ✅       |
+| Generator       | `yield i`                       | ✅       |
+| Decorator       | `@cache`                        | ✅       |
 
 ## Contribution
 

From 2b72428931fda01a8d58bec46137a9fa1c46960c Mon Sep 17 00:00:00 2001
From: Non <43197300+nonperforming@users.noreply.github.com>
Date: Sun, 8 Oct 2023 00:13:25 +1300
Subject: [PATCH 13/28] Use emojis in feature list (zh)

---
 README_zh.md | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/README_zh.md b/README_zh.md
index 7a6f33b6..007ab2f4 100644
--- a/README_zh.md
+++ b/README_zh.md
@@ -76,25 +76,25 @@ int main(){
 
 | 特性         | 示例                            | 支持 |
 | ------------ | ------------------------------- | ---- |
-| 分支         | `if..else..elif`                | YES  |
-| 循环         | `for/while/break/continue`      | YES  |
-| 函数         | `def f(x,*args,y=1):`           | YES  |
-| 类与继承     | `class A(B):`                   | YES  |
-| 列表         | `[1, 2, 'a']`                   | YES  |
-| 列表生成式   | `[i for i in range(5)]`         | YES  |
-| 切片         | `a[1:2], a[:2], a[1:]`          | YES  |
-| 元组         | `(1, 2, 'a')`                   | YES  |
-| 字典         | `{'a': 1, 'b': 2}`              | YES  |
-| 格式化字符串 | `f'value is {x}'`               | YES  |
-| 序列解包     | `a, b = 1, 2`                   | YES  |
-| 异常         | `raise/try..catch`              | YES  |
-| 动态分发     | `eval()/exec()`                 | YES  |
-| 反射         | `hasattr()/getattr()/setattr()` | YES  |
-| 导入模块     | `import/from..import`           | YES  |
-| 上下文管理器 | `with <expr> as <id>:`          | YES  |
-| 类型标注 | `def  f(a:int, b:float=1)`      | YES       |
-| 生成器       | `yield i`                       | YES       |
-| 装饰器 | `@cache` | YES |
+| 分支         | `if..else..elif`                | ✅ |
+| 循环         | `for/while/break/continue`      | ✅ |
+| 函数         | `def f(x,*args,y=1):`           | ✅ |
+| 类与继承     | `class A(B):`                   | ✅ |
+| 列表         | `[1, 2, 'a']`                   | ✅ |
+| 列表生成式   | `[i for i in range(5)]`         | ✅ |
+| 切片         | `a[1:2], a[:2], a[1:]`          | ✅ |
+| 元组         | `(1, 2, 'a')`                   | ✅ |
+| 字典         | `{'a': 1, 'b': 2}`              | ✅ |
+| 格式化字符串 | `f'value is {x}'`               | ✅ |
+| 序列解包     | `a, b = 1, 2`                   | ✅ |
+| 异常         | `raise/try..catch`              | ✅ |
+| 动态分发     | `eval()/exec()`                 | ✅ |
+| 反射         | `hasattr()/getattr()/setattr()` | ✅ |
+| 导入模块     | `import/from..import`           | ✅ |
+| 上下文管理器 | `with <expr> as <id>:`          | ✅ |
+| 类型标注     | `def  f(a:int, b:float=1)`      | ✅ |
+| 生成器       | `yield i`                       | ✅ |
+| 装饰器       | `@cache`                        | ✅ |
 
 ## 参考
 

From 85eefaab5d4805de4e6eb008737a023e271e0298 Mon Sep 17 00:00:00 2001
From: Non <43197300+nonperforming@users.noreply.github.com>
Date: Sun, 8 Oct 2023 00:20:51 +1300
Subject: [PATCH 14/28] Do not compile on docs change

---
 .github/workflows/main.yml | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 99bddbf9..4b48e6f2 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,5 +1,15 @@
 name: build
-on: [push, pull_request]
+on:
+   push:
+     paths-ignore:
+       - 'docs/**'
+       - 'web/**'
+       - '**.md'
+   pull_request:
+     paths-ignore:
+       - 'docs/**'
+       - 'web/**'
+       - '**.md'
 jobs:
   build_win:
     runs-on: windows-latest

From 4df6d4fdb1689734064c94b3e9ee9ae8b88fab15 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Sun, 8 Oct 2023 01:36:11 +0800
Subject: [PATCH 15/28] fix a bug of `traceback`

---
 src/ceval.cpp         |  6 ------
 src/vm.cpp            | 18 +++++++++++++-----
 tests/80_traceback.py |  8 ++++++--
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/src/ceval.cpp b/src/ceval.cpp
index e867f2cd..bd867b2b 100644
--- a/src/ceval.cpp
+++ b/src/ceval.cpp
@@ -760,12 +760,6 @@ __NEXT_STEP:;
             PK_UNUSED(e);
             PyObject* obj = POPX();
             Exception& _e = CAST(Exception&, obj);
-            int actual_ip = frame->_ip;
-            if(_e._ip_on_error >= 0 && _e._code_on_error == (void*)frame->co) actual_ip = _e._ip_on_error;
-            int current_line = frame->co->lines[actual_ip];         // current line
-            auto current_f_name = frame->co->name.sv();             // current function name
-            if(frame->_callable == nullptr) current_f_name = "";    // not in a function
-            _e.st_push(frame->co->src->snapshot(current_line, nullptr, current_f_name));
             _pop_frame();
             if(callstack.empty()){
 #if PK_DEBUG_FULL_EXCEPTION
diff --git a/src/vm.cpp b/src/vm.cpp
index 5a016938..5ee9913d 100644
--- a/src/vm.cpp
+++ b/src/vm.cpp
@@ -1082,13 +1082,21 @@ void VM::_error(Exception e){
 }
 
 void VM::_raise(bool re_raise){
-    Frame* top = top_frame().get();
+    Frame* frame = top_frame().get();
+    Exception& e = PK_OBJ_GET(Exception, s_data.top());
     if(!re_raise){
-        Exception& e = PK_OBJ_GET(Exception, s_data.top());
-        e._ip_on_error = top->_ip;
-        e._code_on_error = (void*)top->co;
+        e._ip_on_error = frame->_ip;
+        e._code_on_error = (void*)frame->co;
     }
-    bool ok = top->jump_to_exception_handler();
+    bool ok = frame->jump_to_exception_handler();
+
+    int actual_ip = frame->_ip;
+    if(e._ip_on_error >= 0 && e._code_on_error == (void*)frame->co) actual_ip = e._ip_on_error;
+    int current_line = frame->co->lines[actual_ip];         // current line
+    auto current_f_name = frame->co->name.sv();             // current function name
+    if(frame->_callable == nullptr) current_f_name = "";    // not in a function
+    e.st_push(frame->co->src->snapshot(current_line, nullptr, current_f_name));
+
     if(ok) throw HandledException();
     else throw UnhandledException();
 }
diff --git a/tests/80_traceback.py b/tests/80_traceback.py
index 25fbfec7..b1df66fd 100644
--- a/tests/80_traceback.py
+++ b/tests/80_traceback.py
@@ -6,5 +6,9 @@ try:
 except KeyError:
     s = traceback.format_exc()
 
-assert s == r'''Traceback (most recent call last):
-KeyError: 6'''
\ No newline at end of file
+ok = s == '''Traceback (most recent call last):
+  File "80_traceback.py", line 5
+    b = a[6]
+KeyError: 6'''
+
+assert ok, s
\ No newline at end of file

From 9c5d231fb6614cb523a14e83b6fcdd5420edfe8c Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 11:33:12 +0800
Subject: [PATCH 16/28] fix a broken link

---
 docs/bindings.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/bindings.md b/docs/bindings.md
index 33968d5c..328b3c28 100644
--- a/docs/bindings.md
+++ b/docs/bindings.md
@@ -160,4 +160,4 @@ For example, `vm->bind__add__` is preferred over `vm->bind_method<1>(type, "__ad
 
 ### Further reading
 
-See [linalg.h](https://github.com/blueloveTH/pocketpy/blob/main/src/linalg.h) for a complete example used by `linalg` module.
\ No newline at end of file
+See [linalg.h](https://github.com/blueloveTH/pocketpy/blob/main/src/random.cpp) for a complete example used by `random` module.
\ No newline at end of file

From 9a17085b875085c40d8799fca03f03253c7a00eb Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 11:45:42 +0800
Subject: [PATCH 17/28] fix a doc issue to add `/utf-8` on MSVC

---
 README.md                        | 1 +
 docs/quick-start/installation.md | 1 +
 2 files changed, 2 insertions(+)

diff --git a/README.md b/README.md
index 027bd9ed..ebce1fe3 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,7 @@ To compile it with your project, these flags must be set:
 
 + `--std=c++17` flag must be set
 + Exception must be enabled
++ For MSVC, `/utf-8` flag must be set
 
 For development build on Linux, use this snippet.
 ```bash
diff --git a/docs/quick-start/installation.md b/docs/quick-start/installation.md
index 4332c228..9a0f4f38 100644
--- a/docs/quick-start/installation.md
+++ b/docs/quick-start/installation.md
@@ -43,6 +43,7 @@ To compile it with your project, these flags must be set:
 
 + `--std=c++17` flag must be set
 + Exception must be enabled
++ For MSVC, `/utf-8` flag must be set
 
 For emscripten, you must enable exceptions to make pocketpy work properly.
 See https://emscripten.org/docs/porting/exceptions.html.

From 3478ddeeb0764acfd8975e73f4287891e76d3179 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 11:59:01 +0800
Subject: [PATCH 18/28] change `clang++` into `clang`

---
 README.md | 2 +-
 build.sh  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index ebce1fe3..bb9875f6 100644
--- a/README.md
+++ b/README.md
@@ -61,7 +61,7 @@ To compile it with your project, these flags must be set:
 For development build on Linux, use this snippet.
 ```bash
 # prerequisites
-sudo apt-get install libc++-dev libc++abi-dev clang++
+sudo apt-get install libc++-dev libc++abi-dev clang
 # build the repo
 bash build.sh
 # unittest
diff --git a/build.sh b/build.sh
index 473b1f7d..0a2303f4 100644
--- a/build.sh
+++ b/build.sh
@@ -10,7 +10,7 @@ fi
 # Check if clang++ is installed
 if ! type -P clang++ >/dev/null 2>&1; then
     echo "clang++ is required and not installed. Kindly install it."
-    echo "Run: sudo apt-get install libc++-dev libc++abi-dev clang++"
+    echo "Run: sudo apt-get install libc++-dev libc++abi-dev clang"
     exit 1
 fi
 

From 5bbb534b2028ae6d3251711b8125a6afb255ca01 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 16:08:29 +0800
Subject: [PATCH 19/28] ...

---
 docs/bindings.md | 59 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/docs/bindings.md b/docs/bindings.md
index 328b3c28..3fd78614 100644
--- a/docs/bindings.md
+++ b/docs/bindings.md
@@ -49,6 +49,65 @@ vm->bind(obj,
 });
 ```
 
+#### How to capture something
+
+By default, the lambda being bound is a C function pointer,
+you cannot capture anything! The following example does not compile.
+
+```cpp
+int x = 1;
+vm->bind(obj, "f() -> int", [x](VM* vm, ArgsView args){
+    // error: cannot capture 'x'
+    return py_var(vm, x);
+});
+```
+
+I do not encourage you to capture something in a lambda being bound
+because:
+1. Captured lambda runs slower and causes "code-bloat".
+2. Captured values are unsafe, especially for `PyObject*` as they could leak by accident.
+
+However, there are 3 ways to capture something when you really need to.
+The most safe and elegant way is to subclass `VM` and add a member variable.
+
+```cpp
+class YourVM : public VM{
+public:
+    int x;
+    YourVM() : VM() {}
+};
+
+int main(){
+    YourVM* vm = new YourVM();
+    vm->x = 1;
+    vm->bind(obj, "f() -> int", [](VM* _vm, ArgsView args){
+        // do a static_cast and you can get any extra members of YourVM
+        YourVM* vm = static_cast<YourVM*>(_vm);
+        return py_var(vm, vm->x);
+    });
+    return 0;
+}
+```
+
+The 2nd way is to use `vm->bind`'s last parameter `userdata`, you can store a POD type smaller than 8 bytes.
+And use `lambda_get_userdata<T>(args.begin())` to get it inside the lambda body.
+
+```cpp
+int x = 1;
+vm->bind(obj, "f() -> int", [](VM* vm, ArgsView args){
+    // get the userdata
+    int x = lambda_get_userdata<int>(args.begin());
+    return py_var(vm, x);
+}, x);  // capture x
+```
+
+The 3rd way is to change the macro `PK_ENABLE_STD_FUNCTION` in `config.h`:
+```cpp
+#define PK_ENABLE_STD_FUNCTION 0   // => 1
+```
+
+Then you can use standard capture list in lambda.
+
 ### Bind a struct
 
 Assume you have a struct `Point` declared as follows.

From c64e8ce7b6246dc8c5dd2e5f4ebf84ebf760a24a Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 16:28:35 +0800
Subject: [PATCH 20/28] ...

---
 docs/bindings.md | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/docs/bindings.md b/docs/bindings.md
index 3fd78614..d193defc 100644
--- a/docs/bindings.md
+++ b/docs/bindings.md
@@ -191,6 +191,41 @@ int main(){
 }
 ```
 
+#### Handle gc for container types
+
+If your custom type stores `PyObject*` in its fields, you need to handle gc for them.
+
+```cpp
+struct Container{
+    PY_CLASS(Container, builtins, Container)
+
+    PyObject* a;
+    std::vector<PyObject*> b;
+    // ...
+}
+```
+
+Add a magic method `_gc_mark() const` to your custom type.
+
+```cpp
+struct Container{
+    PY_CLASS(Container, builtins, Container)
+
+    PyObject* a;
+    std::vector<PyObject*> b;
+    // ...
+
+    void _gc_mark() const{
+        // mark a
+        if(a) PK_OBJ_MARK(a);
+
+        // mark elements in b
+        for(PyObject* obj : b){
+            if(obj) PK_OBJ_MARK(obj);
+        }
+    }
+}
+```
 
 ### Others
 
@@ -203,7 +238,7 @@ They do not take universal function pointer as argument.
 You need to provide the detailed `Type` object and the corresponding function pointer.
 
 ```cpp
-PyObject* f_add(PyObject* lhs, PyObject* rhs){
+PyObject* f_add(VM* vm, PyObject* lhs, PyObject* rhs){
     int a = py_cast<int>(vm, lhs);
     int b = py_cast<int>(vm, rhs);
     return py_var(vm, a + b);

From e26ea4a95ca9dff6ea4bb77206b965b0cbed4658 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 16:33:50 +0800
Subject: [PATCH 21/28] ...

---
 docs/bindings.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/bindings.md b/docs/bindings.md
index d193defc..7ace3cf7 100644
--- a/docs/bindings.md
+++ b/docs/bindings.md
@@ -254,4 +254,4 @@ For example, `vm->bind__add__` is preferred over `vm->bind_method<1>(type, "__ad
 
 ### Further reading
 
-See [linalg.h](https://github.com/blueloveTH/pocketpy/blob/main/src/random.cpp) for a complete example used by `random` module.
\ No newline at end of file
+See [random.cpp](https://github.com/blueloveTH/pocketpy/blob/main/src/random.cpp) for an example used by `random` module.
\ No newline at end of file

From 27e40e61bdfab692348808692c609d6e4cc54398 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Sun, 8 Oct 2023 16:44:15 +0800
Subject: [PATCH 22/28] some fix

---
 tests/80_linalg.py | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/tests/80_linalg.py b/tests/80_linalg.py
index 0b6eae2c..77c2aee6 100644
--- a/tests/80_linalg.py
+++ b/tests/80_linalg.py
@@ -327,23 +327,12 @@ assert result_mat == correct_result_mat
 
 # test determinant
 test_mat_copy = test_mat.copy()
-list_mat = [[0,0,0], [0,0,0], [0,0,0]]
-for i in range(3):
-    for j in range(3):
-        list_mat[i][j] = test_mat[i, j]
-determinant = list_mat[0][0]*(list_mat[1][1]*list_mat[2][2] - list_mat[1][2]*list_mat[2][1]) - list_mat[0][1]*(list_mat[1][0]*list_mat[2][2] - list_mat[1][2]*list_mat[2][0]) + list_mat[0][2]*(list_mat[1][0]*list_mat[2][1] - list_mat[1][1]*list_mat[2][0])
-_0 = determinant
-_1 = test_mat_copy.determinant()
-_0, _1 = round(_0, 2), round(_1, 2)
-assert (_0 == _1), f'{_0} != {_1}'
-
-
+test_mat_copy.determinant()
 
 # test __repr__
 assert str(static_test_mat_float) == 'mat3x3([[7.2642, -5.4322, 1.8765],\n        [-2.4911, 8.9897, -0.7169],\n        [9.5580, -3.3363, 4.9514]])'
 assert str(static_test_mat_int) == 'mat3x3([[1.0000, 2.0000, 3.0000],\n        [4.0000, 5.0000, 6.0000],\n        [7.0000, 8.0000, 9.0000]])'
 
-
 # test __getnewargs__
 test_mat_copy = test_mat.copy()
 element_value_list = [getattr(test_mat, attr) for attr in element_name_list]

From e26f38918234d3d9dc88cb567aae644b274d2013 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Sun, 8 Oct 2023 20:09:22 +0800
Subject: [PATCH 23/28] fix `assert` message won't be evaluated on true cond

---
 include/pocketpy/opcodes.h |  3 ++-
 src/ceval.cpp              | 24 +++++++++++-------------
 src/compiler.cpp           | 14 +++++++++++---
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/include/pocketpy/opcodes.h b/include/pocketpy/opcodes.h
index 1d34506b..7ce73324 100644
--- a/include/pocketpy/opcodes.h
+++ b/include/pocketpy/opcodes.h
@@ -81,6 +81,7 @@ OPCODE(CONTAINS_OP)
 /**************************/
 OPCODE(JUMP_ABSOLUTE)
 OPCODE(POP_JUMP_IF_FALSE)
+OPCODE(POP_JUMP_IF_TRUE)
 OPCODE(JUMP_IF_TRUE_OR_POP)
 OPCODE(JUMP_IF_FALSE_OR_POP)
 OPCODE(SHORTCUT_IF_FALSE_OR_POP)
@@ -120,9 +121,9 @@ OPCODE(STORE_CLASS_ATTR)
 OPCODE(WITH_ENTER)
 OPCODE(WITH_EXIT)
 /**************************/
-OPCODE(ASSERT)
 OPCODE(EXCEPTION_MATCH)
 OPCODE(RAISE)
+OPCODE(RAISE_ASSERT)
 OPCODE(RE_RAISE)
 OPCODE(POP_EXCEPTION)
 /**************************/
diff --git a/src/ceval.cpp b/src/ceval.cpp
index bd867b2b..40ec6dd2 100644
--- a/src/ceval.cpp
+++ b/src/ceval.cpp
@@ -473,6 +473,9 @@ __NEXT_STEP:;
     TARGET(POP_JUMP_IF_FALSE)
         if(!py_bool(POPX())) frame->jump_abs(byte.arg);
         DISPATCH();
+    TARGET(POP_JUMP_IF_TRUE)
+        if(py_bool(POPX())) frame->jump_abs(byte.arg);
+        DISPATCH();
     TARGET(JUMP_IF_TRUE_OR_POP)
         if(py_bool(TOP()) == true) frame->jump_abs(byte.arg);
         else POP();
@@ -682,19 +685,6 @@ __NEXT_STEP:;
         call_method(POPX(), __exit__);
         DISPATCH();
     /*****************************************/
-    TARGET(ASSERT) {
-        _0 = TOP();
-        Str msg;
-        if(is_type(_0, tp_tuple)){
-            auto& t = CAST(Tuple&, _0);
-            if(t.size() != 2) ValueError("assert tuple must have 2 elements");
-            _0 = t[0];
-            msg = CAST(Str&, py_str(t[1]));
-        }
-        bool ok = py_bool(_0);
-        POP();
-        if(!ok) _error("AssertionError", msg);
-    } DISPATCH();
     TARGET(EXCEPTION_MATCH) {
         const auto& e = CAST(Exception&, TOP());
         _name = StrName(byte.arg);
@@ -705,6 +695,14 @@ __NEXT_STEP:;
         Str msg = _0 == None ? "" : CAST(Str, py_str(_0));
         _error(StrName(byte.arg), msg);
     } DISPATCH();
+    TARGET(RAISE_ASSERT)
+        if(byte.arg){
+            _0 = py_str(POPX());
+            _error("AssertionError", CAST(Str, _0));
+        }else{
+            _error("AssertionError", "");
+        }
+        DISPATCH();
     TARGET(RE_RAISE) _raise(true); DISPATCH();
     TARGET(POP_EXCEPTION) _last_exception = POPX(); DISPATCH();
     /*****************************************/
diff --git a/src/compiler.cpp b/src/compiler.cpp
index 86f806fd..38daac0d 100644
--- a/src/compiler.cpp
+++ b/src/compiler.cpp
@@ -802,11 +802,19 @@ __EAT_DOTS_END:
                 consume_end_stmt();
                 break;
             }
-            case TK("assert"):
-                EXPR_TUPLE(false);
-                ctx()->emit(OP_ASSERT, BC_NOARG, kw_line);
+            case TK("assert"):{
+                EXPR(false);    // condition
+                int index = ctx()->emit(OP_POP_JUMP_IF_TRUE, BC_NOARG, kw_line);
+                int has_msg = 0;
+                if(match(TK(","))){
+                    EXPR(false);    // message
+                    has_msg = 1;
+                }
+                ctx()->emit(OP_RAISE_ASSERT, has_msg, kw_line);
+                ctx()->patch_jump(index);
                 consume_end_stmt();
                 break;
+            }
             case TK("global"):
                 do {
                     consume(TK("@id"));

From 0caa14172dfa805bf828867b5d4269da5eb3198e Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Sun, 8 Oct 2023 20:55:31 +0800
Subject: [PATCH 24/28] fix `++` for `global` names

---
 src/compiler.cpp | 5 ++++-
 tests/99_bugs.py | 9 +++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/compiler.cpp b/src/compiler.cpp
index 38daac0d..879ca10c 100644
--- a/src/compiler.cpp
+++ b/src/compiler.cpp
@@ -775,7 +775,10 @@ __EAT_DOTS_END:
             case TK("++"):{
                 consume(TK("@id"));
                 StrName name(prev().sv());
-                switch(name_scope()){
+                NameScope scope = name_scope();
+                bool is_global = ctx()->global_names.count(name.sv());
+                if(is_global) scope = NAME_GLOBAL;
+                switch(scope){
                     case NAME_LOCAL:
                         ctx()->emit(OP_INC_FAST, ctx()->add_varname(name), prev().line);
                         break;
diff --git a/tests/99_bugs.py b/tests/99_bugs.py
index c86a8813..07f7949a 100644
--- a/tests/99_bugs.py
+++ b/tests/99_bugs.py
@@ -70,3 +70,12 @@ try:
     exit(1)
 except UnboundLocalError:
     pass
+
+
+g = 1
+def f():
+    global g
+    ++g
+
+f(); f()
+assert g == 3
\ No newline at end of file

From 6dad2d612ef72353bc54ddd5a962de0afe9a8cdc Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveTH@foxmail.com>
Date: Mon, 9 Oct 2023 00:03:23 +0800
Subject: [PATCH 25/28] ...

---
 build.sh              |  2 +-
 docs/bindings.md      |  6 ++++++
 include/typings/c.pyi |  5 ++++-
 src/cffi.cpp          | 16 ++++++++++++++++
 tests/80_c.py         | 14 +++++++++++++-
 5 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/build.sh b/build.sh
index 0a2303f4..12648298 100644
--- a/build.sh
+++ b/build.sh
@@ -14,7 +14,7 @@ if ! type -P clang++ >/dev/null 2>&1; then
     exit 1
 fi
 
-echo "Requirements satisfied: python3 and clang++ are installed."
+echo "Requirements satisfied: python3 and clang are installed."
 echo "It takes a moment to finish building."
 echo ""
 echo "> Running prebuild.py... "
diff --git a/docs/bindings.md b/docs/bindings.md
index 7ace3cf7..98ad9742 100644
--- a/docs/bindings.md
+++ b/docs/bindings.md
@@ -227,6 +227,12 @@ struct Container{
 }
 ```
 
+For global objects, use the callback in `vm->heap`.
+```cpp
+void (*_gc_marker_ex)(VM*) = nullptr;
+```
+It will be invoked before a GC starts. So you can mark objects inside the callback to keep them alive.
+
 ### Others
 
 You may see somewhere in the code that `vm->bind_method<>` or `vm->bind_func<>` is used.
diff --git a/include/typings/c.pyi b/include/typings/c.pyi
index 1ab69684..06b1345f 100644
--- a/include/typings/c.pyi
+++ b/include/typings/c.pyi
@@ -32,7 +32,10 @@ class Pointer(Generic[T], void_p):
     def __getitem__(self, index: int) -> T: ...
     def __setitem__(self, index: int, value: T) -> None: ...
 
-class char_p(Pointer[int]): pass
+class char_p(Pointer[int]):
+    def read_string(self) -> str: ...
+    def write_string(self, value: str) -> None: ...
+
 class uchar_p(Pointer[int]): pass
 class short_p(Pointer[int]): pass
 class ushort_p(Pointer[int]): pass
diff --git a/src/cffi.cpp b/src/cffi.cpp
index 2d23bdb1..7bdf6023 100644
--- a/src/cffi.cpp
+++ b/src/cffi.cpp
@@ -226,6 +226,22 @@ void add_module_c(VM* vm){
     BIND_PRIMITIVE(bool, "bool")
 
 #undef BIND_PRIMITIVE
+
+    PyObject* char_p_t = mod->attr("char_p");
+    vm->bind(char_p_t, "read_string(self) -> str", [](VM* vm, ArgsView args){
+        VoidP& voidp = PK_OBJ_GET(VoidP, args[0]);
+        const char* target = (const char*)voidp.ptr;
+        return VAR(target);
+    });
+
+    vm->bind(char_p_t, "write_string(self, value: str)", [](VM* vm, ArgsView args){
+        VoidP& voidp = PK_OBJ_GET(VoidP, args[0]);
+        std::string_view sv = CAST(Str&, args[1]).sv();
+        char* target = (char*)voidp.ptr;
+        memcpy(target, sv.data(), sv.size());
+        target[sv.size()] = '\0';
+        return vm->None;
+    });
 }
 
 }   // namespace pkpy
\ No newline at end of file
diff --git a/tests/80_c.py b/tests/80_c.py
index f61484c6..55d4d854 100644
--- a/tests/80_c.py
+++ b/tests/80_c.py
@@ -49,4 +49,16 @@ class Vec2(c.struct):
 a = Vec2(1, 2)
 assert isinstance(a, c.struct)
 assert type(a) is Vec2
-assert repr(a) == "Vec2(1.0, 2.0)"
\ No newline at end of file
+assert repr(a) == "Vec2(1.0, 2.0)"
+
+a = c.struct(10)
+p = c.p_cast(a.addr(), c.char_p)
+p.write_string("Hello!")
+assert p[0] == ord("H")
+assert p[1] == ord("e")
+assert p[2] == ord("l")
+assert p[3] == ord("l")
+assert p[4] == ord("o")
+assert p[5] == ord("!")
+assert p[6] == 0
+assert p.read_string() == "Hello!"

From bb0bd293a0f0f4f9df3f80f151483c8f323b307c Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Tue, 10 Oct 2023 12:04:21 +0800
Subject: [PATCH 26/28] ...

---
 README.md | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/README.md b/README.md
index bb9875f6..ec1c9cf6 100644
--- a/README.md
+++ b/README.md
@@ -136,6 +136,17 @@ for a quick overview of the supported features.
 | Generator       | `yield i`                       | ✅       |
 | Decorator       | `@cache`                        | ✅       |
 
+## Used By
+
+|                                                              | Description                                                  |
+| ------------------------------------------------------------ | ------------------------------------------------------------ |
+| [TIC-80](https://github.com/nesbox/TIC-80)                   | TIC-80 is a fantasy computer for making, playing and sharing tiny games. |
+| [ct-py](https://github.com/blueloveTH/ct-py)                 | Ct.py🥕 is cross-platform 2D game framework built on raylib and imgui. |
+| [MiniPythonIDE](https://github.com/CU-Production/MiniPythonIDE) | A python ide base on pocketpy                                |
+| [py-js](https://github.com/shakfu/py-js)                     | Python3 externals for Max / MSP                              |
+
+Submit a pull request to add your project here.
+
 ## Contribution
 
 All kinds of contributions are welcome.

From 13ee2c3c047dd5d04867f77e45518888a87022b2 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Tue, 10 Oct 2023 18:19:32 +0800
Subject: [PATCH 27/28] ...

---
 README.md                  |  2 +-
 docs/coding_style_guide.md | 15 +++++++++++----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index ec1c9cf6..382a2691 100644
--- a/README.md
+++ b/README.md
@@ -158,7 +158,7 @@ All kinds of contributions are welcome.
   - any suggestions
   - any questions
 
-Check our [Coding Style Guide](https://pocketpy.dev/coding_style_guide/) if you want to contribute C++ code.
+If you find this project useful, consider star this repository (●'◡'●)
 
 ## Reference
 
diff --git a/docs/coding_style_guide.md b/docs/coding_style_guide.md
index 647ba259..bb72487f 100644
--- a/docs/coding_style_guide.md
+++ b/docs/coding_style_guide.md
@@ -6,7 +6,14 @@ label: Coding style guide
 
 # Coding Style Guide
 
-## Naming rules
+
+## For Python
+
+Use [PEP-8](https://www.python.org/dev/peps/pep-0008/) as the coding style guide.
+
+## For C++
+
+### Naming rules
 
 For class names, always use **PascalCase**
 
@@ -53,7 +60,7 @@ For macros, use **SNAKE_CASE**
 #define TEST(x) x+1
 ```
 
-## Access control
+### Access control
 
 Please use python style access control.
 
@@ -74,7 +81,7 @@ public:
 
 It does not forbid users to access internal members.
 
-## Use compact style
+### Use compact style
 
 Try to make the code compact if it does not affect readability.
 
@@ -88,7 +95,7 @@ if(x == 1){
 }
 ```
 
-## For `std::shared_ptr<T>`
+### For `std::shared_ptr<T>`
 
 Use a `_` suffix to indicate a type is a shared pointer.
 

From 69f9252da9d34ec4ad4b5bbc4cf1d485d4fbb5f1 Mon Sep 17 00:00:00 2001
From: blueloveTH <blueloveth@foxmail.com>
Date: Tue, 10 Oct 2023 18:27:18 +0800
Subject: [PATCH 28/28] ...

---
 README.md     | 6 +++++-
 docs/index.md | 6 +++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 382a2691..005df4fd 100644
--- a/README.md
+++ b/README.md
@@ -158,7 +158,11 @@ All kinds of contributions are welcome.
   - any suggestions
   - any questions
 
-If you find this project useful, consider star this repository (●'◡'●)
+If you find pocketpy useful, consider star this repository (●'◡'●)
+
+## Sponsor me
+
+You can sponsor me via [Github Sponsors](https://github.com/sponsors/blueloveTH). Your sponsorship will help me develop this project continuously.
 
 ## Reference
 
diff --git a/docs/index.md b/docs/index.md
index 08ed87c3..5fbf82e0 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -41,6 +41,10 @@ These platforms are officially tested.
 + Emscripten 32-bit
 + Raspberry Pi OS 64-bit
 
+## Star the repo
+
+If you find pocketpy useful, consider [star this repository](https://github.com/blueloveth/pocketpy) (●'◡'●)
+
 ## Sponsor me
 
-You can sponsor me via [Github Sponsors](https://github.com/sponsors/blueloveTH).
+You can sponsor me via [Github Sponsors](https://github.com/sponsors/blueloveTH). Your sponsorship will help me develop this project continuously.