Char literal in a constant expression: ConstEval rejected 'a'

• Type: bug (compiler — const-expression evaluator)
• Status: done
• Owner: Track A
• Opened: 2026-06-21
• Resolved-in: c45b785
• Relation: self-discovered while implementing feature-local-typed-constant. The chess piece-glyph tables (array[..] of Char = ('.', 'P', ...)) need it; the gap also affected GLOBAL char-array typed consts, so it predates the local feature.

Problem

ConstEval (parser.inc) handled integer / boolean / Ord-style ordinals but not a character literal. A single-quoted 'a' lexes as tkString (token Kind 3) of length 1, which fell through to no primary alternative:

const W: array[1..3] of Char = ('a','b','c');
pascal26: Expected: ), but got: a (Kind: 3)
pascal26: error: unexpected token ()

Reproduced on a plain global typed const, so not specific to the local-const work — any const-expression position wanting a char value hit it.

Fix

In ConstEval, add a primary alternative: a length-1 tkString evaluates to its character code (Ord(SVal[1])). Compile-time only; no codegen change.

Acceptance

• const W: array[lo..hi] of Char = ('.', 'P', ...) parses (global and local).
• examples/chess PieceGlyph / MoveText glyph tables compile.

Log

• 2026-06-21 — found + fixed inline during feature-local-typed-constant (c45b785); filed retroactively to document the self-discovered bug. Covered by test/test_local_typed_const.pas (the Char-array case). Track A.