hound-search/hound

Lookaround assertions in regular expressions?

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#305 建立於 2019年2月19日

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 (2 留言) (7 反應) (0 負責人)JavaScript (5,470 star) (606 fork)batch import
enhancementhelp wanted

描述

If I write a regular expression with a (positive or negative) lookahead (or lookbehind) assertion I get an error saying it's incorrect Perl syntax.

For example to look for the text "function" that's not followed by an underscore, I might use this: function(?!_)

However that returns the error: ERROR:error parsing regexp: invalid or unsupported Perl syntax: (?!

However they do work in Perl!

Any ideas?

PS: In this toy example I could use a negated character class function[^_] for searching, but I'm interested in the general case rather than a solution to a specific pattern.

貢獻者指南

技術棧
go
領域
backendsearch
議題類型
feature
難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。
4
預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。
over 1 week
活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。
stale
清晰度議題是否清楚說明預期改動、驗收標準和下一步。
clear
前置要求
Go programmingregular expressionsregex engines
新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。
20
研究方向
Look into the regex parsing code in the hound codebase, likely using Go's regexp package. Determine if there is an alternative regex library that supports lookaheads (e.g., RE2) and evaluate the feasibility of integrating it. Also check if there are existing issues or discussions about this feature.