Package org.ek9lang.compiler.phase0
The Parsing class is used to coordinate the preparation of
the CompilableSource objects state; that are part of the
Workspace.
Each CompilableSource has its own ErrorListener
and error state. The methods:
Are then called in turn for each source file, note that the initial parsing of the source files is multi-threaded. This can be done in a multi-threaded manner because the compiler does not attempt to to cross reference anything.
The Parsing class uses the methods within each
CompilableSource to do the actual parsing.
ParserCreator is used by the CompilableSource
to create the appropriate Ek9LexerForInput and ANTLR based 'EK9Parser'.
The ParserCreator configured both the lexer and the parser in an appropriate
manner (typically error listening).
It is the 'double team' of the Lexer and Parser that opens the file, scans for tokens and then pulls those tokens in to build an in-memory 'AST'. If there is anything wrong in the code at this stage, the errors will be 'ANTLR' style errors.
Only if this phase fully passes for every single source file do the EK9 Compiler continue to the next phase.
This same philosophy applies in all phases, all files must pass each phase before the compiler moves on. Importantly the EK9 Compiler attempts to identify issues in code as early as possible in each phase. It does not attempt to process most of the code to build an 'IR' and then assess the IR. Many of the rules for error detection are contained within each phase. There is an 'IR' generation phase and error assessment, but EK9 attempts to give error feedback as soon as it can.
So you may be thinking 'but where is the state stored'? Basically for phase 0, the
CompilableSource keeps a reference to the 'ANTLR' 'EK9Parser.CompilationUnitContext'.
The CompilableSource is used in most of the other phases in conjunction with
ParsedModule and the CompilableProgram to build uo
state.
The type of symbols that are available from org.ek9lang.compiler.symbols are added to the
appropriate ParsedModule.
See org.ek9lang.compiler.phase1 for the next stage of compilation.
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Classes