mruby does not provide `begin ... end while cond` that behave at-least-once
loop, like CRuby does. It remains in TODO.md for long time. But finally we have
implemented the behavior.
This commit introduces NODE_BEGIN as a distinct AST node type for
explicit begin...end blocks, separate from NODE_STMTS which represents
general statement sequences. This distinction will be essential for
implementing CRuby-compatible begin...end while/until constructs.
Key changes:
- Added NODE_BEGIN enum in node.h
- Added new_begin() function in parse.y using optimized cons() structure
- Modified begin...end grammar rule to generate NODE_BEGIN nodes
- Added NODE_BEGIN codegen support in codegen.c
- Added NODE_BEGIN to parser dump functionality
NODE_BEGIN uses a simpler cons() structure instead of list2() for
better memory efficiency, as it only contains a single body node.
Co-Authored-By: Claude <noreply@anthropic.com>
Rename NODE_BEGIN to NODE_STMTS to better reflect its purpose as a
container for statement sequences, not specifically begin-end blocks.
This prepares for adding a dedicated node type for explicit begin-end
constructs.
- Rename NODE_BEGIN enum to NODE_STMTS in node.h
- Update all references in parse.y and codegen.c
- Rename new_begin function to new_stmts
Co-Authored-By: Claude <noreply@anthropic.com>
Yukihiro "Matz" Matsumoto