Template:For loop
This template is used on approximately 765,000 pages, or roughly 332% of all pages. To avoid major disruption and server load, any changes should be tested in the template's /sandbox or /testcases subpages, or in your own user subpage. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them. |
This template uses Lua: |
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
editParameter | 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
editCode | 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:
|
Lua error: expandTemplate: template "spanbox" does not exist. |
{{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
edit{{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
editThis 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
editThe 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.