// Checks if a variable with type variableType can be set to a variable with type valueType
// (Is [variable = value] a valid statement?)
public static bool CheckTypeCompatibility(string variableType, string valueType, Config config)
{
//Check if types are basic types (number, logical, text) or schemes
if (variableType == VariableTypes.Number)
{
return(valueType == VariableTypes.Number);
}
if (variableType == VariableTypes.Logical)
{
return(valueType == VariableTypes.Logical);
}
if (variableType == VariableTypes.Text)
{
return(valueType == VariableTypes.Text);
}
if (variableType == VariableTypes.Unknown || valueType == VariableTypes.Unknown)
{
return(false);
}
//If variable is 'object', then a value with any object type can be assigned to it
if (variableType == VariableTypes.Object)
{
if (valueType == VariableTypes.Object)
{
return(true);
}
//Basic types are not compatible with 'object'
if (valueType == VariableTypes.Number || valueType == VariableTypes.Logical || valueType == VariableTypes.Text)
{
return(false);
}
Scheme valueScheme = config.GetSchemeByName(valueType);
if (valueScheme == null)
{
throw CreateException($"Unknown type '{valueType}'");
}
return(true);
}
//if variable is of a scheme type
Scheme variableScheme = config.GetSchemeByName(variableType);
if (variableScheme != null)
{
//If scheme exists and the two are equal, they must be compatible
if (variableType == valueType)
{
return(true);
}
//Basic types are not compatible with any scheme
if (valueType == VariableTypes.Number || valueType == VariableTypes.Logical || valueType == VariableTypes.Text)
{
return(false);
}
Scheme valueScheme = config.GetSchemeByName(valueType);
if (valueScheme == null)
{
throw CreateException($"Unknown type '{valueType}'");
}
//Check if the two (different) schemes are compatible (ie. variableType is the ancestor of valueType)
return(valueScheme.HasAncestor(variableType));
}
//if variable type is class type (classlist)
if (config.IsClassType(variableType))
{
return(variableType == valueType);
}
throw CreateException($"Unknown type '{variableType}'");
}
