`str`: Python vs C¶

Python strings differ fundamentally from C strings in storage, safety, and semantics.

C Strings¶

C strings are character arrays terminated by \0:

char str[] = "Hello";  // Actually 6 bytes: H e l l o \0

This leads to:

C has no built-in string length:

// Must scan for null terminator
size_t len = strlen(str);

Python stores length explicitly, no null terminator:

s = "Hello, world!"
length = len(s)
print("Length of the string:", length)  # 13

Python strings are immutable objects:

s = "finance"
print(len(s))   # 7
print(type(s))  # <class 'str'>

Strings cannot be changed in place:

s = "abc"
# s[0] = "A"  # TypeError: 'str' does not support item assignment
s = "A" + s[1:]  # Create new string instead

Immutability enables:

Python handles Unicode naturally:

s = "π ≈ 3.14"
print(s)  # π ≈ 3.14

# Multiple scripts in one string
text = "Hello 世界 مرحبا"
print(len(text))  # Character count, not bytes