SwiftSupport.java 文件源码

/**
 "If an operator has whitespace on the right side only, it is treated as a
 postfix unary operator. As an example, the ++ operator in a++ b is treated
 as a postfix unary operator."
 "If an operator has no whitespace on the left but is followed immediately
 by a dot (.), it is treated as a postfix unary operator. As an example,
 the ++ operator in a++.b is treated as a postfix unary operator (a++ .b
 rather than a ++ .b)."
 */
public static boolean isPostfixOp(TokenStream tokens) {
    int stop = getLastOpTokenIndex(tokens);
    if ( stop==-1 ) return false;

    int start = tokens.index();
    Token prevToken = tokens.get(start-1); // includes hidden-channel tokens
    Token nextToken = tokens.get(stop+1);
    boolean prevIsWS = isLeftOperatorWS(prevToken);
    boolean nextIsWS = isRightOperatorWS(nextToken);
    boolean result =
        !prevIsWS && nextIsWS ||
        !prevIsWS && nextToken.getType()==SwiftParser.DOT;
    String text = tokens.getText(Interval.of(start, stop));
    //System.out.println("isPostfixOp: '"+prevToken+"','"+text+"','"+nextToken+"' is "+result);
    return result;
}