Introspection and platform

These names are always in scope. They are compiler primitives (or module dunders), not import inspect.

typeof(small)              # str
isinstance[i32](small)
isinstance(small, i32)
dir(Box)                   # list[str]
dir()
inspect(scale)             # str
sizeof[i32]()              # i64
alignof[i32]()             # i64
x.__name__  x.__type__  x.__module__  x.__qualname__
Type.__name__

from inspect import label adds extra helpers (label, describe). It does not replace the builtins.

Size and align

sizeof[T]() and alignof[T]() are compile-time facts about the lowered type, returned as i64. Use them when you are writing interop or allocators, not as a substitute for len.

typeof vs isinstance

typeof(x) is a string. isinstance[i32](x) / isinstance(x, i32) is a bool. Unions and aliases follow the type checker, not a runtime class table for primitives.

Platform

Host flags (__windows__, __x86_64__, __platform__, …) are compile-time bools / strings. False if branches are skipped by sema. See Modules.