TODO.md

TODO

The goal is to implement a working Oberon compiler. The checklist below will grow as I go along.

• (temporary) built-in print.
• support simple integers.
• print tokens, AST and IR.
• "golden tests" runner.
• support binary + / -.
• support unary + / -.
• support binary * / /.
• support grouping (...).
• wrap statements in dummy module.
• separate statements and expressions.
• basic type checking.
• support REAL outcome of divisions.
• replace print statement with call expression (still built-in).
• run "golden tests" as unit tests.
• support integer DIV / MOD.
• skip comments in lexer.
• support string literals.
• support boolean literals TRUE / FALSE.
• support logical "not" ~.
• support relational operators = / # / < / <= / >= / >.
• support REAL literals.
• support hex integer literals.
• support hex string literals.
• support scale factor in REAL literals.
• better printing of boolean values.
• support statement sequences (separated by ;).
• get "golden tests" input from the code block in the markdown file.
• remove dedicated "golden test" runner and rely on unit-tests.
• reorganize "golden tests" to combine multiple tiny tests.
• make statement sequence a separate node.
• support basic MODULE structure (excluding imports and declarations) .
• don't panic on compilation errors.
• support IF / THEN / ELSIF / ELSE with constant expressions.
• basic global variable and assignment support.
• support global constant literals.
• support global constant expressions.
• require a MODULE instead of allowing naked statements.
• support built-in INC and DEC procedures.
• support built-in FLT and FLOOR procedures.
• add designator to CallExpr.
• no automatic type conversion.
• support REPEAT / UNTIL statement.
• support WHILE / DO / ELSIF statement.
• support FOR / BY / DO statement.
• support built-in ORD procedure for booleans.
• support CHAR types.
• support built-in ORD and CHR procedures.
• support relational operators for CHAR types.
• support SET types.
• support built-in INCL and EXCL procedures.
• verify SET operations + / - / * / /.
• improve test coverage.
• factor out builtin functions.
• use visitor pattern for builtin functions.
• split code into packages.
• better error reporting.
• continue parsing if errors are found.
• combine constants and vars into symbol-table.
• add types to symbol-table.
• use a type node instead of a token.
• solidify types during type checking.
• support POINTER types.
• support built-in NEW procedure.
• do we need to distinguish lhs / rhs designators?
• support pointer dereferences.
• support temporary built-in DELETE procedure.
• support qualified-identifiers.
• replace print with builtin Texts procedures.
• move generated code to oberonMain to allow for preamble.
• capture command line arguments.
• capture environment variables.
• basic local variable and assignment support.
• generate call-graph in markdown.
• support multiple modules in checker (and generator?).
• better sync points during parser error recovery.
• add "golden tests" for error conditions (e.g. invalid code).
• improve AST and type information for variables.
• support procedure definitions.
• add paramDecl to support by-value vs by-reference parameters.
• add frames in checker (and generator?).
• do we need a new AST for checked nodes?
• support local procedure calls (i.e. in the same module).
• support ARRAY types.
• support built-in LEN procedure.
• support RECORD types.
• support PROCEDURE types.
• support CASE / OF statement.
• make builtin Texts procedures real procedures.
• better command line arguments.
• update "golden test" files in-place, so any additional content doesn't get overwritten.
• support reference counting or garbage collection.
• a magic "C" call built-in module?
• remove builtin print procedure.
• remove builtin DELETE procedure.
• a standard library.
• ...