User talk:Johan G/convert
Parameter value missing
does this template automatically add the to-unit units? in other words, if i "convert|100|mph|kts" will it put kts after the converted number?
also all i can get out of it is like seen on the convert page at the top where it just says "Parameter value missing" but i know they're there... see my experiment here...
--Wkitty42 (talk) 10:58, 4 August 2018 (EDT)
- Hmm. Looking at the template I nearly immediately spotted the problem. I had used named parameters instead of unnamed/numbered parameters (i.e. using
{{{value}}}in the template, requiring the value to be written asvalue=72when "calling" the template instead of just72as was intended).
- With that fixed the issue should be limited to "just" units not yet implemented. :-P
- yes! it is working great! there are some tricks, though...
- when using the template, you must have 5 |'s in the parameters.
- if the exprn has round in it, you have to put a value, even zero, in the decimals field.
- the hide field is the only field that can be empty.
- when editing the template's #exprns, multiplying is done with *
- there is / and div for division. i think one is for integers and the other for whole numbers like in some programming languages
- see here for operands that can be used in #exprns - https://www.mediawiki.org/wiki/Help:Extension:ParserFunctions##expr
i forgot to add, check out my sandbox play with this template here :)
--Wkitty42 (talk) 14:16, 5 August 2018 (EDT)
Architectural ideas
Would using SI base units 
as intermediaries be more maintainable? In essence having subtemplates {{convert/from ''unit''}} to convert to for example convert from statute miles or ounces to meters or kilograms, and subtemplates {{convert/to ''unit''}} to for example convert those to nautical miles and pounds.
Possibly a {{convert/format}} subtemplate for handling decimal precision and whether or not the unit should be hidden.
Regarding parameters, it should be obvious that value, from-unit and to-unit is mandatory and could be unnamed parameters, but parameters for decimal precision and hiding the unit could just as well be named parameters (d for decimals and and h for hide unit perhaps).