December 19, 2022

REPEAT

This element is a static repeat loop. It can be used to repeat several times the same piece of code, with changes managed by an index variable for each instance. There are several ways to define the index for the loop, either with numbers or with a list of strings.

Attributes brief detailed show all inherited

Name	Description	Default
index_name	name of the variable used for the index in the loopfor nested repeats it is necessary to define different names for the index variable to avoid conflicts	index
count	number of repeatsThis is number of repeats for the code contained inside the REPEAT element	0
start	start value for the index published in the repeat loopTo be used with the count attributes. Defines the list of values for the index variable	0
index_list	List of values for the index variable. Also implies the number of repeatsThis attribute overrides the start/count attributes	empty

Name	Value type	Default	Description	Comment
index_name	string	index	name of the variable used for the index in the loop	for nested repeats it is necessary to define different names for the index variable to avoid conflicts
count	integer or a Math Formula using previously defined variables	0	number of repeats	This is number of repeats for the code contained inside the REPEAT element
start	integer or Math Formula using previously defined variables	0	start value for the index published in the repeat loop	To be used with the count attributes. Defines the list of values for the index variable
index_list	list of semi-column separated values (strings)	empty	List of values for the index variable. Also implies the number of repeats	This attribute overrides the start/count attributes

Examples

The following code:

<REPEAT count="2" start="1">
<ELEMENTA attribute_a="$index$"/>
</REPEAT>

Is equivalent to:

<ELEMENTA attribute_a="1"/>
<ELEMENTA attribute_a="2"/>

Similarly, using the index_list attribute instead, the following code:

<REPEAT index_list="A;B">
<ELEMENTA attribute_a="$index$"/>
</REPEAT>

Is equivalent to:

<ELEMENTA attribute_a="A"/>
<ELEMENTA attribute_a="B"/>

And you can modify the index_name attribute for nested loops, so that the following code:

<REPEAT count="2" start="1">
<REPEAT index_name="sub_index" count="2" start="1">
<ELEMENTA attribute_a="$index$-$sub_index$"/>
</REPEAT>
</REPEAT>

Is equivalent to:

<ELEMENTA attribute_a="1-1"/>
<ELEMENTA attribute_a="1-2"/>
<ELEMENTA attribute_a="2-1"/>
<ELEMENTA attribute_a="2-2"/>

A formula can be used to compute the index and start values. For example the following code:

<VARIABLE id="a" value="1">
<VARIABLE id="b" value="0">
<REPEAT count="$a$*2" start="$b$+1">
<ELEMENTA attribute_a="$index$"/>
</REPEAT>

Is equivalent to:

<ELEMENTA attribute_a="2"/>
<ELEMENTA attribute_a="3"/>

Advanced usage

Sometimes you need to increase numeric index as well as loop through the strings in the index_list. You can achieve this using additional VARIABLE with override set to "true". Additionally we can shorten the code using some defines (already defined in LM Skin).

<DEFINE>
<VAR base_type="VARIABLE" override="true" />
<R base_type="REPEAT" />
</DEFINE>
<VAR id="N" value="0" />
<VAR id="list" value="Apples;Peaches;Oranges" />
<VAR id="reversed_list" value="" />
<R index_list="$list$">
<TEXT value="$N$: $index$" />
<VAR id="N" formula="$N$+1" />
<VAR id="reversed_list" value="$index$;$reversed_list$" />
</R>
<TEXT value="$reversed_list$" />

REPEAT as "IF"

Another very useful thing is ability to use formulas in "count" attribute. True = 1, false = 0.

<VAR id="DEBUG_MODE" value="1" />
<R count="$DEBUG_MODE$ != 0">
<TEXT value="Data for DEBUG mode" />
</R>
<R count="$DEBUG_MODE$ == 0">
<TEXT value="Normal mode" />
</R>

However, you can use only numeric and boolean values in formulas. If you need to compare strings, you can use build time scripting possibilities for VARIABLE. Or something! 234

<VAR id="IS_WINDOWS" script="if ("$_SYSTEM_TYPE_$" == "Windows") return "1"; else return "0";" />
<R count="$IS_WINDOWS$">
<TEXT value="We're on Windows" />
</R>
<R count="!$IS_WINDOWS$">
<TEXT value="We're on Mac" />
</R>