Function parseFuncArgs

dql/parser.go:1645–1689

parseFuncArgs will try to parse the arguments inside an array ([]). If the values are prefixed with $ they are treated as Dql variables, otherwise they are used as scalar values. Returns nil on success while appending arguments to the function Args slice. Otherwise returns an error, which can be a p

(it *lex.ItemIterator, g *Function)

// Returns nil on success while appending arguments to the function Args slice. Otherwise
// returns an error, which can be a parsing or value error.
func parseFuncArgs(it *lex.ItemIterator, g *Function) error {
	var expectArg, isDollar bool

	expectArg = true
	for it.Next() {
		item := it.Item()
		switch item.Typ {
		case itemRightSquare:
			return nil
		case itemDollar:
			if !expectArg {
				return item.Errorf("Missing comma in argument list declaration")
			}
			if item, ok := it.PeekOne(); !ok || item.Typ != itemName {
				return item.Errorf("Expecting a variable name. Got: %v", item)
			}
			isDollar = true
			continue
		case itemName:
			// This is not a $variable, just add the value.
			if !isDollar {
				val, err := getValueArg(item.Val)
				if err != nil {
					return err
				}
				g.Args = append(g.Args, Arg{Value: val})
				break
			}
			// This is a $variable that must be expanded later.
			val := "$" + item.Val
			g.Args = append(g.Args, Arg{Value: val, IsDQLVar: true})
		case itemComma:
			if expectArg {
				return item.Errorf("Invalid comma in argument list")
			}
			expectArg = true
			continue
		default:
			return item.Errorf("Invalid arg list")
		}
		expectArg = false
		isDollar = false
	}
	return it.Errorf("Expecting ] to end list but got %v instead", it.Item().Val)
}

// getValueArg returns a space-trimmed and unquoted version of val.
// Returns the cleaned string, otherwise empty string and an error.