Class ParameterisedFunctionCallOrError

java.lang.Object
org.ek9lang.compiler.phase4.ParameterisedFunctionCallOrError
All Implemented Interfaces:
Consumer<PossibleGenericSymbol>
final class ParameterisedFunctionCallOrError extends Object implements Consumer<PossibleGenericSymbol>
Validates that parameterised function call arguments are compatible with substituted parameters.

When a generic function like selectFirst() of type (A, B) is parameterised with concrete types (e.g., A=String, B=Integer), the type arguments are bound positionally from the call site. After type substitution, the function parameters have concrete types. This check verifies that each type argument (which represents the call argument type) is assignable to or promotable to the corresponding substituted parameter type.

Only parameters whose substituted type is directly one of the type arguments are checked. Parameters using complex type expressions (e.g., List of T becoming List of Integer) are skipped because the type argument does not directly represent the call argument type for that parameter position.

Without this check, mismatches are only detected at IR generation where the ParameterPromotionProcessor crashes with a CompilerException instead of a proper diagnostic.