diff options
| -rw-r--r-- | dhall/tests/parser.rs | 2 | ||||
| -rw-r--r-- | dhall_core/src/parser.rs | 16 | ||||
| -rw-r--r-- | dhall_parser/src/dhall.abnf | 12 |
3 files changed, 20 insertions, 10 deletions
diff --git a/dhall/tests/parser.rs b/dhall/tests/parser.rs index fcc2fa9..5f57068 100644 --- a/dhall/tests/parser.rs +++ b/dhall/tests/parser.rs @@ -62,7 +62,7 @@ parser_success!(spec_parser_success_whitespace, "whitespace"); parser_success!(spec_parser_success_whitespaceBuffet, "whitespaceBuffet"); parser_failure!(spec_parser_failure_annotation, "annotation"); -// parser_failure!(spec_parser_failure_builtins, "builtins"); +parser_failure!(spec_parser_failure_builtins, "builtins"); parser_failure!(spec_parser_failure_doubleBoundsNeg, "doubleBoundsNeg"); parser_failure!(spec_parser_failure_doubleBoundsPos, "doubleBoundsPos"); parser_failure!(spec_parser_failure_importAccess, "importAccess"); diff --git a/dhall_core/src/parser.rs b/dhall_core/src/parser.rs index 3f53c49..4f26b0f 100644 --- a/dhall_core/src/parser.rs +++ b/dhall_core/src/parser.rs @@ -266,6 +266,14 @@ make_parser! { [simple_label(l)] => l, [quoted_label(l)] => l, )); + rule!(unreserved_label<Label>; children!( + [label(l)] => { + if Builtin::parse(&String::from(&l)).is_some() { + Err(format!("Builtin names are not allowed as bound variables"))? + } + l + }, + )); rule!(double_quote_literal<ParsedText>; children!( [double_quote_chunk(chunks..)] => { @@ -493,7 +501,7 @@ make_parser! { )); rule!(lambda_expression<ParsedExpr> as expression; children!( - [label(l), expression(typ), expression(body)] => { + [unreserved_label(l), expression(typ), expression(body)] => { bx(Expr::Lam(l, typ, body)) } )); @@ -511,12 +519,12 @@ make_parser! { )); rule!(let_binding<(Label, Option<ParsedExpr>, ParsedExpr)>; children!( - [label(name), expression(annot), expression(expr)] => (name, Some(annot), expr), - [label(name), expression(expr)] => (name, None, expr), + [unreserved_label(name), expression(annot), expression(expr)] => (name, Some(annot), expr), + [unreserved_label(name), expression(expr)] => (name, None, expr), )); rule!(forall_expression<ParsedExpr> as expression; children!( - [label(l), expression(typ), expression(body)] => { + [unreserved_label(l), expression(typ), expression(body)] => { bx(Expr::Pi(l, typ, body)) } )); diff --git a/dhall_parser/src/dhall.abnf b/dhall_parser/src/dhall.abnf index d27554c..02edc84 100644 --- a/dhall_parser/src/dhall.abnf +++ b/dhall_parser/src/dhall.abnf @@ -168,11 +168,13 @@ quoted-label = 1*quoted-label-char ; NOTE: Dhall does not support Unicode labels, mainly to minimize the potential
; for code obfuscation
-; A label cannot not be any of the reserved identifiers for builtins (unless quoted).
+label = ("`" quoted-label "`" / simple-label)
+
+; An unreserved-label cannot not be any of the reserved identifiers for builtins (unless quoted).
; Their list can be found in semantics.md. This is not enforced by the grammar but
; should be checked by implementations. The only place where this restriction applies
; is bound variables.
-label = ("`" quoted-label "`" / simple-label)
+unreserved-label = label
; An any-label is allowed to be one of the reserved identifiers.
any-label = label
@@ -541,7 +543,7 @@ expression = / annotated-expression
; "\(x : a) -> b"
-lambda-expression = lambda whitespace "(" whitespace label whitespace ":" nonempty-whitespace expression ")" whitespace arrow whitespace expression
+lambda-expression = lambda whitespace "(" whitespace unreserved-label whitespace ":" nonempty-whitespace expression ")" whitespace arrow whitespace expression
; "if a then b else c"
ifthenelse-expression = if nonempty-whitespace expression then nonempty-whitespace expression else nonempty-whitespace expression
@@ -550,10 +552,10 @@ ifthenelse-expression = if nonempty-whitespace expression then nonempty-whitespa ; "let x = e1 in e2"
; "let x = e1 let y = e2 in e3"
let-expression = 1*let-binding in nonempty-whitespace expression
-let-binding = let nonempty-whitespace label whitespace [ ":" nonempty-whitespace expression ] "=" whitespace expression
+let-binding = let nonempty-whitespace unreserved-label whitespace [ ":" nonempty-whitespace expression ] "=" whitespace expression
; "forall (x : a) -> b"
-forall-expression = forall whitespace "(" whitespace label whitespace ":" nonempty-whitespace expression ")" whitespace arrow whitespace expression
+forall-expression = forall whitespace "(" whitespace unreserved-label whitespace ":" nonempty-whitespace expression ")" whitespace arrow whitespace expression
; "a -> b"
arrow-expression = operator-expression arrow whitespace expression
|