Method expandTupleArgs

compiler/utils.go:132–149

expandTupleArgs converts a function call which argument is a tuple returned by another function into a set of individual call arguments corresponding to tuple elements. For example, for functions defined as: func a() (int, string) {return 42, "foo"} func b(a1 int, a2 string) {} ...the following

(argExprs []ast.Expr)

//	_tuple := a()
//	b(_tuple[0], _tuple[1])
func (fc *funcContext) expandTupleArgs(argExprs []ast.Expr) []ast.Expr {
	if len(argExprs) != 1 {
		return argExprs
	}

	tuple, isTuple := fc.typeOf(argExprs[0]).(*types.Tuple)
	if !isTuple {
		return argExprs
	}

	tupleVar := fc.newLocalVariable("_tuple")
	fc.Printf("%s = %s;", tupleVar, fc.translateExpr(argExprs[0]))
	argExprs = make([]ast.Expr, tuple.Len())
	for i := range argExprs {
		argExprs[i] = fc.newIdent(fc.formatExpr("%s[%d]", tupleVar, i).String(), tuple.At(i).Type())
	}
	return argExprs
}

func (fc *funcContext) translateArgs(sig *types.Signature, argExprs []ast.Expr, ellipsis bool) []string {
	argExprs = fc.expandTupleArgs(argExprs)