Method pushInvoke

src/main/java/wyil/check/FlowTypeCheck.java:1772–1803

(int var, Expr.Invoke expr, Typing typing, Environment environment)

	}

	private Typing pushInvoke(int var, Expr.Invoke expr, Typing typing, Environment environment) {
		// Extract link
		Decl.Link<Decl.Callable> link = expr.getLink();
		// Save argument expressions for later
		Tuple<Expr> arguments = expr.getOperands();
		final int n = arguments.size();
		// Select candidates with matching numbers of arguments
		List<Decl.Callable> candidates = select(link.getCandidates(), c -> c.getParameters().size() == n);
		// Check this invocation is resolvable
		if (!link.isPartiallyResolved() || candidates.size() == 0) {
			syntaxError(link.getName(), AMBIGUOUS_CALLABLE, link.getCandidates());
			return typing.invalidate();
		}
		// Allocate space for the signature variables. This is used to identify each row
		// in the typing matrix with one of candidates.
		typing = typing.push(Type.Any).push(Type.Any).push(Type.Any);
		int v_concrete = typing.top();
		int v_template = v_concrete - 1;
		int v_signature = v_concrete - 2;
		// Register a finaliser to resolve this invocation
		typing.register(typeInvokeExpression(expr, v_signature, v_template));
		// Fork typing into different cases for each overloaded candidate
		typing = typing
				.project(row -> fork(candidates, c -> initialiseCallableFrame(row, expr, c, v_signature, v_concrete, v_template)));
		// <<< Filter return type
		Typing nTyping = typing.map(
				row -> filterOnSubtype(row, var, row.get(v_concrete).as(Type.Callable.class).getReturn(), environment));
		// Sanity check whether valid typing still possible
		checkForError(expr, typing, nTyping, var, v_concrete, t -> getLambdaReturn(t));
		// >>> Propagate forwards into children
		return pushExpressions(arguments, (r, i) -> getLambdaParameter(r.get(v_concrete), i), nTyping, environment);
	}

	private Typing pushLambdaAccess(int var, Expr.LambdaAccess expr, Typing typing, Environment environment) {
		Decl.Link<Decl.Callable> link = expr.getLink();