Kiroha 0.3 → 0.4: explicit named functions

This is the historical 0.3 → 0.4 guide. For current syntax, continue with 0.4 → 0.5.

Kiroha 0.4.0 makes the start and end of each named function explicit:

fun fac(n) then
  if n <= 1 then 1 else n * fac(n - 1)
end fun fac;
fac(5)    // 120

The closing name must exactly match the opening name, including case. All of end, fun, and the name are required. Each nested function closes with its own name. The parser rejects a missing or mismatched delimiter before any program effects run.

In 0.3, the corresponding definition was fac(n)=if n<=1 then 1 else n*fac(n-1). Replace the bare header with fun fac(n) then, and append end fun fac after the old body. Old bare definitions and fun fac(n)=... are invalid. Calls retain their existing spelling: fac(5).

A body is now a sequence, so local bindings do not require a do wrapper:

fun apply_twice(x){body} then
  y = body(x);
  body(y)
end fun apply_twice;
apply_twice(2){x => x * 3}   // 18

A sequence returns its last expression; an empty body or a body ending in a binding or definition returns null. A trailing semicolon is permitted. Parameters, the callback-slot name and body locals share a scope. A local binding cannot redeclare a parameter; an explicit do still creates a child scope. An old do body can be retained to preserve that child scope. Named recursion, lexical capture, static resolution, callback channels and proper tail calls keep their existing behavior.

fun and end are now reserved: rename variables, functions, parameters or callback slots that used either word. Record keys still allow reserved words, including {fun:1,end:2}, r.fun, and r?.end. Strings, comments and SQL text are unaffected.

The choice follows the language author's preliminary experiment with named end markers for generation. Token measurements describe source length; they do not independently establish a generation-quality improvement.

The CLI and conformance wire formats remain kiroha-cli/1 and kiroha-conformance/1. Language metadata is now 0.4.0 / 0.4.0/Web1. Use the installer to select a release; 0.3 programs require migration or a pinned 0.3.0 executable.