Files
sx/examples/0040-basic-block-value.sx
agra d8076b9333 lang: rename signed integer types sN -> iN
Surface rename of the signed integer family: s1..s64 become i1..i64
(u1..u64, usize, isize unchanged). 'string' keeps the s-prefix arm in
name classification; width parsing moves to the i-prefix arm next to
isize.

Internal TypeId tags follow the surface (.s8/.s16/.s32/.s64 ->
.i8/.i16/.i32/.i64), as do mono-key mangle fragments (ptr_i64,
tu_i64_bool) and all display/diagnostic formatting (i{d}).

Migrated in the same sweep: stdlib + examples + issue repros + FFI C
companions (shared symbol names like ffi_id_i64), expected
stdout/stderr/ir snapshots, specs.md, readme.md, CLAUDE.md/AGENTS.md,
implementation_plan.md, docs/, issue writeups. Vendored stb_image and
historical flow state left untouched.

zig build test: 426/426; examples suite: 595/595.
2026-06-12 09:31:53 +03:00

47 lines
1.5 KiB
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// Block value rule: a block's value is its last statement ONLY when that
// statement is a trailing expression with NO `;`. A trailing `;` discards the
// value, leaving the block void. This makes value-vs-statement explicit and lets
// the compiler reject "forgot to produce a value".
//
// { … expr } → value is `expr`
// { … expr; } → void (value discarded)
//
// Match arms are exempt: the arm `;` is an arm terminator, so `case .x: expr;`
// still yields `expr` (only an explicit inner braced block follows the rule).
#import "modules/std.sx";
// Implicit return: trailing expression, no `;`.
double :: (n: i32) -> i32 { n * 2 }
// if/else as a value — each branch's last expression has no `;`.
sign :: (n: i32) -> i32 {
if n < 0 { -1 } else if n > 0 { 1 } else { 0 }
}
// A value-producing block bound to a name.
sum3 :: (a: i32, b: i32, c: i32) -> i32 {
t := { x := a + b; x + c }; // block value is `x + c`
t
}
// Match arms keep their `;` (exempt): the arm `;` is an arm terminator, so each
// arm still yields its expression as the match value.
classify :: (n: i32) -> i32 {
if n == {
case 0: 100;
case 1: 10;
else: 7;
}
}
main :: () -> i32 {
total : i32 = 0;
total = total + double(10); // 20
total = total + sign(-7); // -1
total = total + sum3(1, 2, 3); // 6
total = total + classify(1); // 10
print("block-value total: {}\n", total); // 20 - 1 + 6 + 10 = 35
total
}