Re: [xsl] Effects of white space between xml elements

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

Nat,

Hermann has offered you the solution. You also asked whether white 
space between tags in XML source wasn't (shouldn't be) ignored in the 
transformation.

The answer is no. In the general case, XML parsers are not supposed 
to strip any whitespace at all, in the expectation that without a 
schema, it can't know which white space matters, and which white 
space doesn't. For example, in an element like

<p>He sent her roses <i>and</i> <b>chocolate</b>.</p>

you wouldn't want the whitespace between the 'i' and the 'b' elements 
to be stripped.

This general rule is however subject to a number of caveats:

* Some XML processors ignore it: caveat emptor. (For example, MSXML 
is famous for this.)
* In XSLT 2.0, where schema-aware processing can be supported, a 
source tree can be pruned of insignificant whitespace nodes, on the 
basis of schema declarations that mandate treating whitespace as cosmetic.

For example, in your data, if there were a schema or DTD declaration 
for 'actions' that said it could contain only 'effect', or at any 
rate not contain text (#PCDATA), then it would be known statically 
that whitespace didn't count, and a processor could discard it for you.

In addition, even in XSLT 1.0 there are top-level instructions, 
xsl:strip-space and xsl:preserve-space, which allow you to control 
this directly.

I hope this helps,
Wendell

At 06:16 PM 2/23/2009, you wrote:
> <xsl:for-each select="child::*"> does what you want.
>
> "child::node()" matches the (white space) text nodes in addition.
...

> Does white space between elements of an xml document effect the output
> of a transformation of that document?  I noticed that sometimes adding
> a new line in between the closing tag of one element and the opening
> tag of the next element changes my output, even though I am working
> with the same stylesheet.
>
> I thought that white space in an XML document was ignored during the
> transformation; that the only thing that will effect the output are
> the on/off tags and how they are nested in each other.  If tags are
> nested properly, shouldn't white space and new lines in between
> elements be irrelevant?


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