Statements

Statements are the unit of control flow. The parser covers def, class, struct, enum, type, macro, imports, if / while / for / match / try, defer, del, assert, raise, and assignment. On error it synchronizes and keeps going so the LSP can still highlight the rest of the file.

Simple statements

pass
assert cond
assert cond, "failed"
return expr
break
continue
n = n + 1
n += 2
++n
n++

assert False, "fail" raises a catchable AssertionError. pass is a no-op suite filler.

if / while / for

if n == 1:
    n = n + 2
elif n == 0:
    pass
else:
    n = -n

while n < 4:
    n = n + 1

for n in range(0, 4):
    total += n
for item in xs:
    total += item
for ch in hello:
    pass

for iterates range(...), str (one-character strings), and list[T]. A false compile-time host branch is not typechecked:

if __windows__:
    windows.message_box("hi")

That is how OS-only APIs stay off other targets. See Modules.

defer

defer free(raw)
defer:
    print("done")

defer queues its body and runs it in reverse order on every return, including the implicit return at the end of the function. Use it for free, unlock, and “always log” — not as a substitute for finally on exceptions. Exception paths are try / finally.

del

del xs[i]
del table[key]

Removes a list index or dict key. del name is a diagnostic. There is no unbind-a-local form.

with

with Guard() as value:
    print(value)

One evaluated context object. The type must define __enter__ and __exit__. as value binds the enter result.

match

See Pattern matching. match is a statement. Arms are case suites, optionally with if guards.