Here is how to check if the string "abcde" is exactly 5 characters:
{{str ≠ len | abcde | 5
| Not equal.
| Equal.
}}
Which returns this:
Equal.
Templates have a problem to handle parameter data that contains equal signs "=". But that is easily solved by using numbered parameters. Here we check if the string "ab=cde" is exactly 100 characters:
It probably is a good habit to always use the numbered parameters, since you might not know beforehand exactly how the data will look that your template will feed to this meta-template.
Parameters
Detailed parameter explanation:
{{str ≠ len
| 1 = A string
| 2 = A length
| 3 = Data to return/render when "not equally long".
| 4 = Data to return/render when "equally long".
}}
Empty or undefined strings are considered to be of 0 length.
Length values below 0 are considered to be 0.
Technical details
This template would be equivalent to templates named {{str != len}} or {{str == len}}, but we can't use those template names since they don't work well in MediaWiki.
Templates have problems to handle parameter data that contains pipes "|", unless the pipe is inside another template {{name|param1}} or inside a piped link [[Help:Template|help]]. Thus templates can not handle wikitables as input unless you escape them by using the {{!}} template. This makes it hard to use wikitables as parameters to templates. Instead the usual solution is to use "HTML wikimarkup" for the table code, which is more robust.
