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Precedence but it doesn't work

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Tree sitter doesn't let me do token-based precedence? I don't like
tree-sitter's "make it inline but give it a number" system- seems like
a bug farm to me.
This commit is contained in:
John Doty 2024-08-31 07:22:49 -07:00
parent 98c4bb950f
commit 3012df4ac6
3 changed files with 35 additions and 14 deletions
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27
parser/tree_sitter.py
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@ -99,9 +99,21 @@ def to_javascript_regex(re: parser.Re) -> str:
raise Exception(f"Regex node {re} not supported for tree-sitter")
def convert_to_tree_sitter(rule: parser.Rule, grammar: parser.Grammar) -> str:
# TODO: Precedence?
def apply_precedence(js: str, name: str, grammar: parser.Grammar) -> str:
prec = grammar.get_precedence(name)
if prec is not None:
assoc, level = prec
if assoc == parser.Assoc.LEFT:
js = f"prec.left({level}, {js})"
elif assoc == parser.Assoc.RIGHT:
js = f"prec.right({level}, {js})"
else:
js = f"prec({level}, {js})"
return js
def convert_to_tree_sitter(rule: parser.Rule, grammar: parser.Grammar) -> str:
method = getattr(rule, "convert_to_tree_sitter", None)
if method is not None:
return method(grammar)
@ -109,10 +121,14 @@ def convert_to_tree_sitter(rule: parser.Rule, grammar: parser.Grammar) -> str:
if isinstance(rule, parser.Terminal):
if isinstance(rule.pattern, parser.Re):
regex = to_javascript_regex(rule.pattern)
return f"/{regex}/"
result = f"/{regex}/"
else:
string = to_js_string(rule.pattern)
return f'"{string}"'
result = f'"{string}"'
if rule.name is not None:
result = apply_precedence(result, rule.name, grammar)
return result
elif isinstance(rule, parser.AlternativeRule):
final = []
@ -176,7 +192,6 @@ def convert_to_tree_sitter(rule: parser.Rule, grammar: parser.Grammar) -> str:
# https://tree-sitter.github.io/tree-sitter/creating-parsers
def emit_tree_sitter_grammar(grammar: parser.Grammar, path: pathlib.Path | str):
# TODO: PRECEDENCE
path = pathlib.Path(path) / "grammar.js"
with open(path, "w", encoding="utf-8") as f:
f.write('/// <reference types="tree-sitter-cli/dsl" />\n')
@ -195,6 +210,8 @@ def emit_tree_sitter_grammar(grammar: parser.Grammar, path: pathlib.Path | str):
body = rule.fn(grammar)
rule_definition = convert_to_tree_sitter(body, grammar)
rule_definition = apply_precedence(rule_definition, rule.name, grammar)
f.write(f" '{rule_name}': $ => {rule_definition},")
f.write(" }\n")