Re: [xsl] XSLT Regex for Matching Curly Braces

["Liam R. E. Quin liam@xxxxxxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

On Mon, 2019-06-10 at 18:21 +0000, Don Smith
dsmith_lockesmith@xxxxxxxxx wrote:
>  Thank you all,
> I used Gerrit's suggestion <xsl:analyze-string select="."
> regex="\{{([^}}]+)\}}"> and it appears to work exactly as desired. 

As an addendum, i'll add that i tend to use [{] and [}] and the same
for [(] and [)] so as not to have to worry about regular expression
engines in which those are or aren't special -- in some, \( \) are for
capturing and \{ \} are for counting, for example.

So i end up with
  [{](^{}]+)[}]

This is marginally less efficient than \{ and \} but that seldom
matters in practice.

I used [^{}] partly to avoid nested braces and partly because then the
automatic brace matching in my editor will show the close one matching
with the open one, and thatbs a feature that tends to reduce errors.

Sometimes i use variables for bra and ket in XSLT, e.g. if ibm making
CSS or JavaScript or something.

But that's a separate issue from embedding them in XSLT and dealing
with { } being for attribute value templates :) and Mike Kaybs solution
is (unsurprisingly) the best for that.

For a really complex expression, use the x flag:

<xsl:variable as="xs:string" name="within-braces">
    [{]      <!--* opening bace *-->
    (        <!--* $1 *-->
      [^{}]+ <!--* not containing a brace *-->
    )        <!--* end $1 *-->
    [}]      <!--* closing brace *--> 
</xsl:variable>

and then fn:replace($input, $within-braces, 'x'), or more likely,
  <xsl:analyze-string regex="$within-braces" flags="x" . .. . >


Liam


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