//
// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// result.c -- Contains the expected value or an error value.
//
// Author           : Andrew Beach
// Created On       : Wed May 24 15:40:00 2017
// Last Modified By : Andrew Beach
// Last Modified On : Thr May 25 15:27:00 2017
// Update Count     : 1
//

#include <containers/result>
#include <assert>


forall(otype T, otype E)
void ?{}(result(T, E) * this) {
	this->has_value = false;
	(&this->error){};
}

forall(otype T, otype E)
void ?{}(result(T, E) * this, one_t, T value) {
	this->has_value = true;
	(&this->value){value};
}

forall(otype T, otype E)
void ?{}(result(T, E) * this, zero_t, E error) {
	this->has_value = false;
	(&this->error){error};
}

forall(otype T, otype E)
void ?{}(result(T, E) * this, result(T, E) other) {
	this->has_value = other.has_value;
	if (other.has_value) {
		(&this->value){other.value};
	} else {
		(&this->error){other.error};
	}
}

forall(otype T, otype E)
result(T, E) ?=?(result(T, E) * this, result(T, E) that) {
	if (this->has_value & that.has_value) {
		this->value = that.value;
	} else if (this->has_value) {
		^(&this->value){};
		this->has_value = false;
		(&this->error){that.error};
	} else if (that.has_value) {
		^(&this->error){};
		this->has_value = true;
		(&this->value){that.value};
	} else {
		this->error = that.error;
	}
}

forall(otype T, otype E)
void ^?{}(result(T, E) * this) {
	if (this->has_value) {
		^(&this->value){};
	} else {
		^(&this->error){};
	}
}

forall(otype T, otype E)
bool ?!=?(result(T, E) this, zero_t) {
	return this.has_value;
}

forall(otype T, otype E)
result(T, E) result_value(T value) {
	return (result(T, E)){1, value};
}

forall(otype T, otype E)
result(T, E) result_error(E error) {
	return (result(T, E)){0, error};
}

forall(otype T, otype E)
bool has_value(result(T, E) * this) {
	return this->has_value;
}

forall(otype T, otype E)
T get(result(T, E) * this) {
	assertf(this->has_value, "attempt to get from result without value");
	return this->value;
}

forall(otype T, otype E)
E get_error(result(T, E) * this) {
	assertf(!this->has_value, "attempt to get from result without error");
	return this->error;
}

forall(otype T, otype E)
void set(result(T, E) * this, T value) {
	if (this->has_value) {
		this->value = value;
	} else {
		^(&this->error){};
		this->has_value = true;
		(&this->value){value};
	}
}

forall(otype T, otype E)
void set_error(result(T, E) * this, E error) {
	if (this->has_value) {
		^(&this->value){};
		this->has_value = false;
		(&this->error){error};
	} else {
		this->error = error;
	}
}