Template:For loop/doc

Template:For loop implements a for loop or a foreach loop.

This template calls a user-specified template (the "called template") once for each value in either 1) an iterated sequence or 2) an explicit list. A specified parameter of the called template is passed each value in the sequence or list (with optional pre- and postfixes attached). The first unnamed parameter of this template (the "separator") is output between calls to the called template. In addition to the one variable-valued parameter, other "static" parameters of the called template can be passed, with the same value in each iteration.

Usage

Parameter	Value	Notes
1 (unnamed)	separator to output between calls (whitespace is preserved)	MANDATORY (may be blank)
call	template to call	MANDATORY
pv	name of the variable parameter to pass to the called template	MANDATORY unless it is the first unnamed parameter of the called template (use integers for other unnamed parameters)
pc[N]n	name (or number) of the Nth static parameter to pass to the called template
pc[N]v	value of the Nth static parameter to pass to the called template
prefix	static prefix prepended to each of the variable values
postfix	static postfix appended to each of the variable values
substall	false to not substitute the called template when {{for loop}} is substituted (defaults to true)
start	first value to pass to variable parameter (defaults to 1)	Option 1: iterator
stop	maximum value for variable parameter
by	iteration step size between values passed to variable parameter (defaults to 1)
(unnamed)	explicit list of variable values, given as separate parameters (whitespace is stripped)	Option 2: explicit values
skipBlanks	true to skip empty parameter values (defaults to false)

Note that either iterator parameters (option 1) or an explicit list of values (option 2) may be used, but not both.

The separator is the first unnamed parameter, allowing it to start and/or end with newlines and spaces. The separator is output between calls to the template named in |call=. It is not output after the last call to that template. The separator parameter is prior to the value list. If a value in the list contains an equals sign, use {{=}} (see Help:Template). If you do not use {{=}}, the list must use named parameters, at least from that point. If you use named parameters, note that the first value is parameter 2 (e.g. |2=Your1stValue), because parameter 1 is the separator. If the separator contains an equals sign, {{=}} should also be used. Alternately, the separator can similarly be prefixed with "1=", but in that case it cannot contain newlines and spaces at the start and end. Also, if you use named parameters, you must not skip any numbers. The loop will terminate after the first absent numbered parameter. (Note that parameters can be blank but not absent; blank parameters are read as normal.)

Examples

Code	Explanation	Result
{{for loop|&|call = spanbox |pc1n = 1 |pc1v = A |pc2n = background |pc2v = yellow |pv = font size |postfix = px |start=10|stop=52|by=8 }}	Outputting "&" between calls, call the template "spanbox" with values: 1 (first unnamed parameter) = "A" background = "yellow" font size = "[N]px", where N takes values starting with 10 and increasing by 8 while remaining less than or equal to 52
{{for loop|, |call=1x |prefix=1 |00|01|02|03|04|05|06|07|08|09 |10|11|12|13|14|15|16|17|18|19 |20|21|22|23|24|25|26|27|28|29 |30|31|32|33|34|35|36|37|38|39 |40|41|42|43|44|45|46|47|48|49 |50|51|52|53|54|55|56|57|58|59 |60|61|62|63|64|65|66|67|68|69 |70|71|72|73|74|75|76|77|78|79 |80|81|82|83|84|85|86|87|88|89 |90|91|92|93|94|95|96|97|98|99 }}	Call the template "1x" with values "1[NN]", where NN = "00" through "99" (given explicitly), separating the outputs with the string ", "	100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199

Other examples

{{for loop|-|a|3||c|g|call=3x}} using Template:3x (backlinks, edit) gives

aaa-333-ccc-ggg

{{for loop|

|a|3||c|g|call=3x}} gives

aaa

333

ccc

ggg

{|class="wikitable sortable"
|-
!Test
|-
| {{for loop|
{{!}}-
{{!}} |a|b|c|d|e|call=3x}}
|}

gives:

Test
aaa
bbb
ccc
ddd
eee

{{for loop| |01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|16|17|18|19
|20|21|22|23|24|25|26|27|28|29|30|31|32|33|34|35|36|37|38|39
|40|41|42|43|44|45|46|47|48|49|50|51|52|53|54|55|56|57|58|59
|60|61|62|63|64|65|66|67|68|69|70|71|72|73|74|75|76|77|78|79
|80|81|82|83|84|85|86|87|88|89|90|91|92|93|94|95|96|97|98|99
|100|101|102|103|104|105|106|107|108|109|110|111|112|113|114|115|116|117|118|119
|120|121|122|123|124|125|126|127|128|129|130|131|132|133|134|135|136|137|138|139
|140|141|142|143|144|145|146|147|148|149|150|151|152|153|154|call=1x}}

gives:

01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154

begin->{{for loop|{{=}} |01|02|03|04|05|06|07|08|09|10
|11{{=}}{{=}}{{=}}|12|13|14|15|16|17|18|19|call=1x}}<-end

gives:

begin->01= 02= 03= 04= 05= 06= 07= 08= 09= 10= 11==== 12= 13= 14= 15= 16= 17= 18= 19<-end

Legacy code

This template is currently in its third incarnation. It now uses the Lua code at Module:ForLoop. It was ported to Lua from ParserFunctions. There was also a previous version with a named "sep" parameter to specify the separator value. The template was originally based on m:Template:For. The template name was changed because there was already a Template:For on Wikipedia.

The old versions were limited to 150 variable values and four fixed parameters. There are no such limits in the current version. Also, in the first version the "sep" parameter didn't allow whitespace in the separator value. This was fixed with the second version and was retained in the current version.

Substitution

The current Lua-based template supports substitution. If |substall=no is not specified, then substituting the template will substitute everything, including the call to the template passed in |call=. If it is specified, then the template substitutes into a sequence of calls to the template specified.

Example: {{subst:for loop|sep|01|02|03|04|...}} -> 01sep 02sep 03sep 04sep 05sep 06sep 07, {{subst:for loop|sep|01|02|03|04|...}} -> {{1x|01}}sep {{1x|02}}sep {{1x|03}}sep {{1x|04}}sep {{1x|05}}sep {{1x|06}}sep {{1x|07}}

For full substitution Special:ExpandTemplates can also be used.

See also

• mw:Template:Fe
• m:Template:foreach (backlinks, edit)
• m:Template:tblb (backlinks, edit)
• Template:for nowiki (backlinks, edit)
• Template:item (backlinks, edit)
• Template:loop (backlinks, edit)
• Template:simple recursion (backlinks, edit)
• Help:Parameter default
• Help:Array
• mw:Extension:LoopFunctions