Beefy Boxes and Bandwidth Generously Provided by pair Networks
"be consistent"
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??

I would have used regular expression pattern matching for this seemingly trivial text substitution (insertion) problem. The formatting of the XML is quite regular and straightforward. Both the string you're matching and the string you're replacing (enhancing) it with are distinct and uncomplicated. You say you "had a hell of a time getting XPath to work." I wouldn't have had the patience to try.

You're explicitly handling both the input text and the output text as binary data rather than as Unicode text? Why?

Here's the operation reduced to a Unicode-conformant one-liner:

C:\Temp>perl -CiO -i.bak -pe "s{(?<=[/\\]ReleaseDLL)(?=[/\\])}{32} if +m{^\s*<(?:Out|Int)Dir>}" fred.vcxproj C:\Temp>diff fred.vcxproj.bak fred.vcxproj 9,10c9,10 < <OutDir>.\../../products/bin/ReleaseDLL\</OutDir> < <IntDir>.\ReleaseDLL\</IntDir> --- > <OutDir>.\../../products/bin/ReleaseDLL32\</OutDir> > <IntDir>.\ReleaseDLL32\</IntDir> 15,16c15,16 < <OutDir>.\../../products/bin/ReleaseDLL\</OutDir> < <IntDir>.\ReleaseDLL\</IntDir> --- > <OutDir>.\../../products/bin/ReleaseDLL32\</OutDir> > <IntDir>.\ReleaseDLL32\</IntDir> C:\Temp>od -h -N 3 fred.vcxproj 0000000000 EF BB BF 0000000003 C:\Temp>

Modify the anchoring regular expression patterns to taste.

Doing it this way avoids the needless and undesirable reordering of the attributes of the <Project> element—and a lot of other XML folderol besides. It also handles the input and output properly as Unicode text rather than as binary data and leaves the existing UTF-8 byte order mark intact.

Modifying this one-liner to support file and folder name globs (wildcards) is left as an exercise for the reader.

UPDATE:  With modern versions of Perl, you can use the special look-behind assertion \K to obviate the separate pattern match used to anchor the substitution (insertion) to just those lines that have <OutDir> and <IntDir> elements on them.

C:\>perl -CiO -i.bak -pe "INIT { @ARGV = <@ARGV> } s{^\s*<(?:Out|Int)D +ir>.+?[/\\]ReleaseDLL\K}{32}" */*.vcxproj C:\>diff Temp\fred.vcxproj.bak Temp\fred.vcxproj 9,10c9,10 < <OutDir>.\../../products/bin/ReleaseDLL\</OutDir> < <IntDir>.\ReleaseDLL\</IntDir> --- > <OutDir>.\../../products/bin/ReleaseDLL32\</OutDir> > <IntDir>.\ReleaseDLL32\</IntDir> 15,16c15,16 < <OutDir>.\../../products/bin/ReleaseDLL\</OutDir> < <IntDir>.\ReleaseDLL\</IntDir> --- > <OutDir>.\../../products/bin/ReleaseDLL32\</OutDir> > <IntDir>.\ReleaseDLL32\</IntDir> C:\>

In reply to Re: Some questions from beginning user of XML::LibXML and XPath by Jim
in thread Some questions from beginning user of XML::LibXML and XPath by eyepopslikeamosquito

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • Outside of code tags, you may need to use entities for some characters:
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others cooling their heels in the Monastery: (6)
    As of 2014-08-20 11:27 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      The best computer themed movie is:











      Results (111 votes), past polls