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lualua-patterns

Any Lua pattern alternative to the regex (\\.|.)?

There's a common idiom for traversing a string whose characters may be escaped with a backslash by using the regex (\\.|.), like this:

alert( "some\\astring".replace(/(\\.|.)/g, "[$1]") )

That's in JavaScript. This code changes the string some\astring to [s][o][m][e][\a][s][t][r][i][n][g].

I know that Lua patterns don't support the OR operator, so we can't translate this regular expression directly into a Lua pattern.

Yet, I was wondering: is there an alternative way to do this (traversing possibly-escaped characters) in Lua, using a Lua pattern?

Solution

  • You can try

    (\\?.)

    and replace with [$1]

    See it on Regexr.

    ? is a shortcut quantifier for 0 or 1 occurences, so the above pattern is matching a character and an optional backslash before. If ? is not working (I don't know lua) you can try {0,1} instead. That is the long version of the same.