ANTLR4-在JavaScript语法中解析regex文本

Question

我只剩下一个问题：我不知道如何处理RegEx文本的转角情况，如下所示：

log(Math.round(v * 100) / 100 + ' msec/sample');

/100+'msec/被解释为RegEx文本，因为lexer规则始终处于活动状态。

我想要的是合并这个逻辑(C#代码。我需要JavaScript，但我不知道如何修改它）：

    /// <summary>
    /// Indicates whether regular expression (yields true) or division expression recognition (false) in the lexer is enabled.
    /// These are mutual exclusive and the decision which is active in the lexer is based on the previous on channel token.
    /// When the previous token can be identified as a possible left operand for a division this results in false, otherwise true.
    /// </summary>
    private bool AreRegularExpressionsEnabled
    {
        get
        {
            if (Last == null)
            {
                return true;
            }

            switch (Last.Type)
            {
                // identifier
                case Identifier:
                // literals
                case NULL:
                case TRUE:
                case FALSE:
                case THIS:
                case OctalIntegerLiteral:
                case DecimalLiteral:
                case HexIntegerLiteral:
                case StringLiteral:
                // member access ending 
                case RBRACK:
                // function call or nested expression ending
                case RPAREN:
                    return false;

                // otherwise OK
                default:
                    return true;
            }
        }
    }

RegularExpressionLiteral
    : { AreRegularExpressionsEnabled }?=> DIV RegularExpressionFirstChar RegularExpressionChar* DIV IdentifierPart*
    ;

Answer 1

我在这里发布最终的解决方案，它将现有的解决方案与ANTLR4的新语法相适应，并解决了JavaScript语法中的差异。

我只是张贴相关的部分，给其他人一个关于工作策略的线索。

规则编辑如下：

RegularExpressionLiteral
    : DIV {this.isRegExEnabled()}? RegularExpressionFirstChar RegularExpressionChar* DIV IdentifierPart*
    ;

@members {
EcmaScriptLexer.prototype.nextToken = function() {
  var result = antlr4.Lexer.prototype.nextToken.call(this, arguments);
  if (result.channel !== antlr4.Lexer.HIDDEN) {
    this._Last = result;
  }

  return result;
}

EcmaScriptLexer.prototype.isRegExEnabled = function() {
  var la = this._Last ? this._Last.type : null;
  return la !== EcmaScriptLexer.Identifier &&
    la !== EcmaScriptLexer.NULL &&
    la !== EcmaScriptLexer.TRUE &&
    la !== EcmaScriptLexer.FALSE &&
    la !== EcmaScriptLexer.THIS &&
    la !== EcmaScriptLexer.OctalIntegerLiteral &&
    la !== EcmaScriptLexer.DecimalLiteral &&
    la !== EcmaScriptLexer.HexIntegerLiteral &&
    la !== EcmaScriptLexer.StringLiteral &&
    la !== EcmaScriptLexer.RBRACK &&
    la !== EcmaScriptLexer.RPAREN;
}}