#ifndef COERCION_H
#define COERCION_H

#include "types.h"
#include "Node.h"
#include "SyntaxTree.h"

/* Gives the ReturnType that is at least needed for binary operators
 * based on the return types of the left and right hand sides. 
 */
ReturnType minimumtype(ReturnType lhs, ReturnType rhs);

/* Check whether type is of expected type 
 */
void checkType(ReturnType expected, ReturnType actual);
void checkType(ReturnType expected, Node *expression);


/* Coerces the expression node if necessary.
 * Returns either a coercion node or expression itself.
 */
Node *coerce(ReturnType to, Node *expression);

/* Checks if the number and type of the arguments to the call are correct
 * and coerces arguments if necessary.
 * It gives an error message if it is incorrect.
 * call_node must be a valid NodeType of either NODE_FUNCTIONCALL or
 * NODE_PROCCALL
 */
void check_parameters(Node *call_node);

#endif /* COERCION_H */