strings:ReplaceVariables

note

This article is about the strings:ReplaceVariables Blend function.

• System-named attributes
• User-named attributes
• Pattern attributes for substitution based on regular expressions

strings:ReplaceVariables

In an input text, replaces all occurrences of a set of text strings, or matches of regular-expression patterns, by target values. The replacements required are provided as replacement instructions.

Returns the replaced text.

Syntax

Namespace declaration

You need to declare this namespace only if you call the function directly from the USCSXSL component but outside Blend. In a Blend context (ublendit.exe, uscsxsl.blend()) the namespace is already declared in the Blend transformation, which is in xsl\Util\Batch.1.0.xsl in your USoft installation folder.

xmlns:strings="USoft:Strings"

Function call

strings:ReplaceVariables(
*input-text*
, *replace-instruction*
  [{
   , *name-attribute-name*
   , *value-attribute-name*
   , *pattern-attribute-name*
  }]
)

*replace-instruction*  ::=

  <*top-level-element*>
    <*instruction-element   name-attribute  pattern-attribute   value-attribute*  />
    <*instruction-element   name-attribute  pattern-attribute   value-attribute*  />
    ...

  </*top-level-element*>

The required input-text is a regular text string, for example, a SQL statement.

The required replace-instruction is an XML fragment containing a single top-level-element and any number of child instruction-elements. 0 instruction elements is legal but will have no effect.

You can pass input parameters to the replacement routine by using variable references in the replace-instruction.

What each instruction-element must look like depends on whether you are passing name-attribute-name, value-attribute-name and pattern-attribute-name or not. Either NONE of these 3 arguments must be passed, or ALL 3 must be passed as single-quoted string literals, in which case the single-quoted empty string ( '' ) is a valid option.

System-named attributes

If none of the 3 optional arguments is passed, each instruction-element must have an attribute named NAME (with capitals) and an attribute named VALUE (with capitals).

In place of the NAME attribute you can have a PATTERN attribute, or you can have both a NAME and a PATTERN attribute. See the "Pattern attributes" section later in this article.

Example

<example xmlns:pc="Processing.Command" pc:hideme="true" >
<pc:defs>
     update book set published_in = 'English' where author = 'English'; update book set published_in = 'American' where author = 'American';
</pc:defs>
<pc:defs>
   <Languages>
      <LANGUAGE_CODE NAME="eng" VALUE="en"/>
        <LANGUAGE_CODE NAME="English" VALUE="eng-GB"/>
        <LANGUAGE_CODE NAME="American" VALUE="eng-US"/>
    </Languages>
</pc:defs>
<pc:assign-string   input_text=    "{//pc:defs[1]}"/>
<pc:assign-nodeset  replacements=  "{//pc:defs[2]/*}"/>
<pc:assign-string   replaced_text="{strings:ReplaceVariables($input_text,$replacements)}" />

<pc:value-of select="$replaced_text"/>

</example>

The result is:

update book set published_in = 'en-GB' where author = 'en-GB'; update book set published_in = 'en-US' where author = 'en-US';

User-named attributes

If all of the 3 optional arguments are passed, each instruction-element in replace-instruction must have:

• an attribute by the name of name-attribute-name, or an attribute by the name of pattern-attribute-name, or both, and :
• an attribute by the name of value-attribute-name.

Example

<example xmlns:pc="Processing.Command" pc:hideme="true" >
<pc:defs>
     update book set published_in = 'English' where author = 'English'; update book set published_in = 'American' where author = 'American';
</pc:defs>
<pc:defs>
   <Languages>
      <LANGUAGE_CODE language="eng" code="en"/>
        <LANGUAGE_CODE language="English" code="eng-GB"/>
        <LANGUAGE_CODE language="American" code="eng-US"/>
    </Languages>
</pc:defs>
<pc:assign-string   input_text=    "{//pc:defs[1]}"/>
<pc:assign-nodeset  replacements=  "{//pc:defs[2]/*}"/>
<pc:assign-string   replaced_text="{strings:ReplaceVariables($input_text,$replacements, 'language', 'code', '')}" />

<pc:value-of select="$replaced_text"/>

</example>

The result is:

update book set published_in = 'en-GB' where author = 'en-GB'; update book set published_in = 'en-US' where author = 'en-US';

Pattern attributes for substitution based on regular expressions

The above examples showed simple string substitutions because pattern-attribute-name was empty.

If pattern-attribute-name is non-empty, then all text occurrences that match any of the values of pattern-attribute-name (considered as regular-expression patterns) are replaced by the corresponding value-attribute-name.

If both name-attribute-name and pattern-attribute-name are non-empty, replacements on the basis of the regular-expression patterns occur first, followed by replacements on the basis of the hard-coded strings.

Example

<example xmlns:pc="Processing.Command" pc:hideme="true" >
<pc:defs>
     ID: 18900, RGB: grey red; ID: 18901, RGB: gray red;
</pc:defs>
<pc:defs>
   <colours>
      <colour en="red" de="rot" />
      <colour en_pattern="gr[a|e]y" de="grau" />
    </colours>
</pc:defs>
<pc:assign-string    input_text=    "{//pc:defs[1]}"/>
<pc:assign-nodeset   replacements=  "{//pc:defs[2]/*}"/>
<pc:assign-string    replaced_text="{strings:ReplaceVariables($input_text,$replacements, 'en', 'de', 'en_pattern')}" />

<pc:value-of select="$replaced_text"/>

</example>

The result is:

ID: 18900, RGB: grau rot; ID: 18901, RGB: grau rot;