Function parseMatchExpr

src/e9tool/e9action.cpp:802–853

* Parse a match expr. */

 * Parse a match expr.
 */
static MatchExpr *parseMatchExpr(Parser &parser, int prec = 99)
{
    MatchExpr *expr = nullptr;
    int t = parser.peekToken();
    switch (t)
    {
        case '(':
            (void)parser.getToken();
            expr = parseMatchExpr(parser);
            parser.expectToken(')');
            break;
        case '!': case TOKEN_NOT:
            (void)parser.getToken();
            expr = parseMatchExpr(parser, 10);
            expr = new MatchExpr(MATCH_OP_NOT, expr);
            break;
        case TOKEN_NONE:
            (void)parser.getToken();
            expr = parseMatchExpr(parser, 0);
            break;
        case '~': case '-':
            (void)parser.getToken();
            expr = parseMatchExpr(parser, 0);
            expr = new MatchExpr((t == '-'? MATCH_OP_NEG: MATCH_OP_BIT_NOT),
                expr);
            break;
        case TOKEN_DEFINED:
            (void)parser.getToken();
            parser.expectToken('(');
            expr = parseMatchExpr(parser);
            parser.expectToken(')');
            expr = new MatchExpr(MATCH_OP_DEFINED, expr);
            break;
        default:
        {
            auto arg = parseMatchArg(parser);
            expr = new MatchExpr(MATCH_OP_ARG, arg);
            break;
        }
    }
    while (true)
    {
        int t = parser.peekToken();
        const MatchOpInfo *info = parseMatchOp(t);
        if (info == nullptr || info->prec > prec)
            break;
        (void)parser.getToken();
        MatchExpr *arg = parseMatchExpr(parser, info->prec-1);
        expr = new MatchExpr(info->op, expr, arg);
    }
    return expr;
}

/*
 * Parse a match expr.