Add ##method() syntax to call a method on the input object

kevinmehall · Dec 3, 2018 · 1f3418c · 1f3418c
1 parent c58d620
commit 1f3418c
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Showing 3 changed files with 9 additions and 1 deletion.
diff --git a/peg-codegen/grammar.rs b/peg-codegen/grammar.rs
diff --git a/peg-codegen/grammar.rustpeg b/peg-codegen/grammar.rustpeg
@@ -156,6 +156,7 @@ primary -> Spanned<Expr>
   / class
   / "." { AnyCharExpr }
   / "@" { MarkerExpr }
+  / "##" _ method:identifier _ "(" args:$((!")" .)*) ")" { MethodExpr(method, args.to_owned()) }
   / "#position" { PositionExpr }
   / "#quiet" _ "<" _ e:expression _ ">" { QuietExpr(Box::new(e)) }
   / "#expected" _ "(" _ s:doubleQuotedString _ ")" { FailExpr(s) }

diff --git a/peg-codegen/translate.rs b/peg-codegen/translate.rs
@@ -216,6 +216,7 @@ pub enum Expr {
 	LiteralExpr(String),
 	PatternExpr(String),
 	RuleExpr(String),
+	MethodExpr(String, String),
 	SequenceExpr(Vec<Spanned<Expr>>),
 	ChoiceExpr(Vec<Spanned<Expr>>),
 	OptionalExpr(Box<Spanned<Expr>>),
@@ -598,6 +599,12 @@ fn compile_expr(compiler: &mut PegCompiler, cx: Context, e: &Spanned<Expr>) -> T
 			}
 		}
 
+		MethodExpr(ref method, ref args) => {
+			let method = raw(method);
+			let args = raw(args);
+			quote!{ __input.#method(__pos, #args) }
+		}
+
 		TemplateInvoke(ref name, ref params) => {
 			let template = match cx.grammar.templates.get(&name[..]) {
 				Some(x) => x,