Help:Array: Difference between revisions

Revision as of 02:33, 19 December 2005

Revision as of 22:31, 12 January 2006

Line 2:

This pages explains various methods of creating a kind of [[w:en:associative array|associative array]] using [[Help:Template|templates]].

Note that producing an array element for a given index value corresponds to a case statement or switch.

==Main array technique==

This method of creating a data array using [[Help:Template|templates]] seems to be the most suitable and is therefore recommended.

==Array technique using parameter defaults==

An example of an array is {{tim|short DOW}}, containing:

{{tim|Short DOW alt 2}} contains (without the newlines):

<pre>

{{{if{{{1|u}}}|Mon}}}

{{{if{{{2|u}}}|Tue}}}

{{{if{{{3|u}}}|Wed}}}

{{{if{{{4|u}}}|Thu}}}

{{{if{{{5|u}}}|Fri}}}

{{{if{{{6|u}}}|Sat}}}

{{{if{{{0|u}}}|Son}}}

</pre>

<nowiki>{{short DOW alt 2|ifu=|3=}}</nowiki> gives {{short DOW alt 2|ifu=|3=}}

<nowiki>{{short DOW alt 2|ifu=|6=|3=|5=|3=}}</nowiki> gives {{short DOW alt 2|ifu=|6=|3=|5=|3=}}

The results are in the index order according to the template content, not in the order of the parameters in the template call. Multiple occurrences are removed.

==Array technique using a small auxiliary template==

Example:

<nowiki>{{array</nowiki>

|index=''index''

|1=Mon

|2=Tue

|3=Wed

|4=Thu

|5=Fri

|6=Sat

|0=Sun

}}

It usesusing {{tim|array}}, containing <code><nowiki>{{{{{{index}}}|{{{default|}}}}}}</nowiki></code>.

In the case of a constant ''index'' this can be useful for selection from predetermined options by a small edit. Alternatively ''index'' can be an expression depending on a variable, or, if the text is in a template, on a parameter.

Note that if only one template is used, the difference with the method above is that the array data are outside the template: they are provided in the template call.

Example where the text is in another template (with also a default value): {{tim|short DOW}}, containing:

----

<pre>{{array

Line 19 ⟶ 57:

}}</pre>

----

It uses {{tim|array}}, containing <code><nowiki>{{{{{{index}}}|{{{default|}}}}}}</nowiki></code>.

Examples:

Line 62 ⟶ 98:

<code><nowiki>{{foreach|call=Short DOW|sep=-|3|{{CURRENTDOW}}|7}}</nowiki></code> gives "{{foreach|call=Short DOW|sep=-|3|{{CURRENTDOW}}|7}}"

<code><nowiki>{{foreach|call=Short DOW|6|3|5|3}}</nowiki></code> gives "{{foreach|call=Short DOW|6|3|5|3}}"

Compare the array technique using parameter defaults, above.

Differences:

*Above only one template is used instead of three.

*Above the results are in standard index order, here in the order of the parameters in the template call.

*Above multiple occurrences are removed.

==Method of erasing specification for erasure==

Line 317 ⟶ 362:

==See also==

*[[w:en:Wikipedia talk:Avoid using meta-templates#Logic templates|Logic templates]] (discussion)

*[[w:en:Portal:Middle-earth/Featured article]] called in [[w:en:Portal:Middle-earth]] - array technique based on [[Help:parameter default|parameter default]]s

{{h:f|enname=Array}}