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Selective execution

XML
<switch value="string">
    <case value="string">ixml</case>
    <default>ixml</default>
</switch>

The <switch /> construct is a control flow structure that allows for selective execution of code controlled via a multiway branch. It can be thought of as a series of IF constructs, each with the same value to compare from.

If the value of a <switch /> statement equals the value of an embedded CASE statement, the control flow continues with the execution of that CASE statement. Otherwise, the control flow continues with the execution of the embedded DEFAULT statement.

Attention:

Comparison of numeric values is always performed numerically regardless of the intrinsic data types.

It is in some cases desirable, for a branch to intentionally fall through to the next branch, thereby creating a cascading execution stack. For that prupose the NEXT operation may be used to skip the rest of the current CASE statement and continue with the execution of the next consecutive CASE statement inside the same paternal SWITCH statement. Also, the BREAK operation may be used to break-off the execution of the current CASE or DEFAULT statement and continue with the execution outside the paternal SWITCH statement.

SWITCH will propagate results into the context of its paternal statement.

Attributes

NameTypeDescriptionDefined By
valuestringValue to compare from switch

Children​

case
XML
<case value="string">ixml</case>

Attributes

NameTypeDescription
valuestringValue to compare to
default
XML
<default>ixml</default>

Examples

Basic branch

XML
<set var="lastname">Gates</set>

<switch value="$lastname">
  <case value="Gates">
    <output>My name might be Bill Gates!</output>
  </case>
  
  <case value="Jobs">
    <output>My name might be Steve Jobs!</output>
  </case>
  
  <default>
    <output>My name is not Bill Gates nor Steve Jobs!</output>
  </default>
</switch>

<!-- My name might be Bill Gates! -->

Fall-through branch

XML
<set var="firstname">Steve</set>
<set var="lastname">Gates</set>

<switch value="$lastname">
  <case value="Gates">
    <if value1="$firstname" func="=" value2="Steve">
      <next/>
    </if>
    
    <output>My name might be Bill Gates!</output>
  </case>
  
  <case value="Jobs">
    <output>My name might be Steve Jobs!</output>
  </case>
</switch>

<!-- My name might be Steve Jobs! -->