Add multi-dimensional static array syntax, both the comma form
(array[0..1, 0..2] of Integer; A[i, j]) and the equivalent nested/chained
form (array[0..1] of array[0..2] of Integer; A[i][j]). The comma forms are
syntactic sugar: the parser desugars array[a, b] of T into the nested
array[a] of array[b] of T, and A[i, j] into chained subscripts A[i][j], so
the two notations are fully interchangeable in every position.
Layers:
- uParser: comma loops in ParseTypeName and subscript reads; the statement
LHS now lowers A[i, j] := v and A[i][j] := v to a TStaticSubscriptAssign
carrying a new BaseExpr (the inner-array address expression). The previous
"chained base not yet supported" rejection is removed.
- uAST: TStaticSubscriptAssign.BaseExpr (owned); wired into CloneStmt and the
.bif encoder/decoder (uUnitInterfaceIO); bif-coverage status updated.
- uSemantic: BaseExpr branch resolves the inner static-array type and checks
the index and value element type.
- Codegen (both backends): a nested static-array element now evaluates to its
inline address (mirroring record/interface elements) so a further subscript
indexes into it; the static-subscript store reads its base from BaseExpr
when set. Nested arrays are a flat row-major contiguous block.
- OPDF: no new record needed - each dimension emits one recArray whose element
points at the next inner recArray; pdr follows the chain and renders the
value as a true multi-dimensional structure.
Tests: IR unit tests (cp.test.staticarray), e2e tests on both backends via
AssertRunsOnAll (cp.test.e2e.staticarray), and a nested-recArray OPDF test
(cp.test.opdf). Grammar and language rationale documented.