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NonWellformedType

rascal-0.34.0

Synopsis​

A type in a declaration is not wellformed.

Description​

Types should respect some structural rules and this error signals a violation of these rules. Examples of violations are:

  • a non-parametric type has parameters.
  • a parametric type has an incorrect number of parameters.

Remedy: correct the type.

Examples​

rascal>bool[int] x;
|prompt:///|(0,4,<1,0>,<1,4>): Non-well-formed type: bool cannot have type arguments.
Advice: |https://www.rascal-mpl.org/docs/Rascal/Errors/CompileTimeErrors/NonWellformedType|
ok
rascal>list[int,str] l;
|prompt:///|(0,4,<1,0>,<1,4>): Non-well-formed type: list should have exactly one type argument, like list[value]
Advice: |https://www.rascal-mpl.org/docs/Rascal/Errors/CompileTimeErrors/NonWellformedType|
ok
rascal>map[str, int, int]  m;
|prompt:///|(0,3,<1,0>,<1,3>): Non-well-formed type: map should have exactly two type arguments, like map[value,value]
Advice: |https://www.rascal-mpl.org/docs/Rascal/Errors/CompileTimeErrors/NonWellformedType|
ok
rascal>set[int,str] s;
|prompt:///|(0,3,<1,0>,<1,3>): Non-well-formed type: set should have exactly one type argument, like set[value]
Advice: |https://www.rascal-mpl.org/docs/Rascal/Errors/CompileTimeErrors/NonWellformedType|
ok
  • bool does not have type parameters
  • list only has one element type. Perhaps you needed a lrel[int, str]?
  • map has the key and the value type parameters, but not more
  • set has only one element type. Perhaps you needed a rel[int, str]?