raesl.compile.parser

Parsing the Elephant Specification Language.

Module Contents

Classes

LineMachineStepper

Class managing parsing of a line in ESL.

Functions

parse_line(...)	Parse a text-line in ESL.
parse_lexer(...)	Parse an ESL lexer, storing collected information in the builder.
parse_spec(...)	Parse an ESL specification, storing collected information in the builder.
collect_locations(...)	Collect the set reachable states from 'spec_state' without taking only 'epsilon'

class raesl.compile.parser.LineMachineStepper(machine: raesl.compile.machine_files.builder.ProcessingStateMachine, lexer: raesl.compile.scanner.Lexer, dest_loc: raesl.compile.state_machine.Location)

Class managing parsing of a line in ESL.

Parameters:

• machine – Line matching machine to use for recognizing the line.

• lexer – Lexer to use in the matching process.

• current_loc – Current location in the line machine.

• tags – Relevant data extracted from the text line during the parsing process.

• matched_tokens – Tokens used for matching the line thus far.

• dest_loc – New specification location if a match was found.

try_step() → bool

Try to match the next token.

Returns:

Whether progress was made.

is_accepting() → bool

Is the machine in an accepting location?

get_accept_name() → str

Get the acceptance name associated with the accepting location.

Returns:

Name of the accepted ‘rule’.

raesl.compile.parser.parse_line(spec_state: raesl.compile.state_machine.Location, lexer: raesl.compile.scanner.Lexer, builder: raesl.compile.typechecking.ast_builder.AstBuilder, diag_store: raesl.compile.diagnostics.DiagnosticStore) → Tuple[raesl.compile.state_machine.Location | None, raesl.compile.scanner.Lexer | None]

Parse a text-line in ESL.

For debugging line selection, set scanner.PARSER_DEBUG to True, which enables printing debug information to the std output. For best results, use a small input specification, output is quite verbose.

Parameters:

• spec_state – Location in the ESL language state machine.

• lexer – Lexer pointing at the start of the next line to match.

• builder – Class storing extracted parse data.

• diag_store – Storage for reported diagnostics.

Returns:

Next state in the ESL state machine unless successfully finished, next lexer to use if next step can be performed.

raesl.compile.parser.parse_lexer(lexer: raesl.compile.scanner.Lexer, diag_store: raesl.compile.diagnostics.DiagnosticStore | None, builder: raesl.compile.typechecking.ast_builder.AstBuilder | None, doc_comments: List[raesl.compile.scanner.Token] | None) → Tuple[raesl.compile.diagnostics.DiagnosticStore, raesl.compile.typechecking.ast_builder.AstBuilder, List[raesl.compile.scanner.Token], bool]

Parse an ESL lexer, storing collected information in the builder.

Parameters:

• lexer – Lexer pointing at the start of the specification text.

• diag_store – Diagnostic store if one already has been created.

• builder – Builder if one already has been created.

• doc_comments – Doc comments if any have been found yet.

Returns:

Diagnostic store instance. Builder instance. Found doc comments. Whether there has been an error.

raesl.compile.parser.parse_spec(lexers: Iterable[raesl.compile.scanner.Lexer], diag_store: raesl.compile.diagnostics.DiagnosticStore | None = None) → Tuple[raesl.compile.diagnostics.DiagnosticStore, raesl.compile.ast.specification.Specification | None]

Parse an ESL specification, storing collected information in the builder.

Parameters:

lexers – Lexers pointing at the start of their respective texts (e.g. per-file).

Returns:

The found diagnostics, and if successful, the type-checked output.

raesl.compile.parser.collect_locations(spec_state: raesl.compile.state_machine.Location) → List[raesl.compile.state_machine.Location]

Collect the set reachable states from ‘spec_state’ without taking only ‘epsilon’ transitions.