fix: allow expressions inside list constructors (GH #135)

[toddr-bot]

What

Expressions with operators (concatenation, arithmetic, comparison, boolean, ternary) now work inside [...] list constructors.

Why

Fixes GH #135. The parser grammar restricted list elements to simple terms (identifiers, literals, numbers), so [ 'foo' _ 'bar' ] threw "unexpected token (_)" and [ 1 + 2 ] threw "unexpected token (+)". The workaround was assigning to a variable first, which was unintuitive.

How

Changed the list production rule in Parser.yp from list term to list expr, allowing any expression as a list element. Regenerated Grammar.pm via yapp. The change introduces 3 additional shift/reduce conflicts in the LALR tables, all correctly resolved by the existing operator precedence declarations. Range syntax [1 .. 5] and space-separated lists [1 2 3] continue to work — the parser greedily consumes operators, so [1 + 2 3] correctly produces [3, 3].

Testing

• 9 new test cases in t/list.t covering: string concatenation, arithmetic, division, comparison, ternary, variable expressions, NOT, and boolean operators in list constructors
• Full test suite: 2910 tests pass, 0 regressions

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🤖 Generated with Claude Code

[toddr-bot]

Recreated from #372 (auto-closed when the toddr-bot fork was removed). Original branch is now hosted on this repo.

[toddr]

@toddr-bot rebase

[toddr-bot]

Rebase with requested adjustments

Branch koan.toddr.bot/fix-list-expr-parsing was rebased onto main and review feedback was applied.

Stats

3 files changed, 4135 insertions(+), 4057 deletions(-)

Actions performed

• Already-solved check: negative (confidence=high, reasoning=Parser.yp on main still uses 'term' in list production rule; no commit addresses GH Parser can't handle list constructor around string concatenation [rt.cpan.org #117863] #135 or list con)
• Resolved merge conflicts (1 round(s))
• Rebased koan.toddr.bot/fix-list-expr-parsing onto origin/main
• Pre-push CI check: previous run passed
• Force-pushed koan.toddr.bot/fix-list-expr-parsing to origin
• CI check enqueued in ## CI (async)

CI status

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