Meteor-handlebar-helpers
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raix
$mapped doesn't work with arrays of non-objects
Yes, because current implementation of $mapped has nothing to do with non-object values and tries to extend primitives.
I believe this is implementation issue. There are some other issues that don't work for me, so I've created a package for similar purpose, gonna try to keep it updated.
Hey @raix, here's a first draft.
Template.registerHelper('$mapped', function(arr) {
return _.map(arr, function(item, index) {
/* jshint -W053 */
// In this case we explicitly want String to be used as a constructor, so that we can add properties to it.
var strObj = new String(item + 'abc');
/* jshint +W053 */
strObj.$first = index === 0;
strObj.$index = index;
strObj.$last = index === arr.length-1;
return strObj;
});
});
The only caveat is that in the template, instead of {{ this }} returning a raw string, it returns a String object which is then automatically cast to its String value. So, if a developer passes 'this' in the template context to some other function, it will be different than usually expected.
You could add a variable 'thisRaw' on strObj to allow the caller access to the raw string, which works but adds a slight cognitive load to anyone who uses $mapped.
The jshint directive is necessary because it's generally not ok to use new for a primitive constructor, but in this case we need to build an actual object.
A maybe-cleaner way to do this would be to inject variables into the data context, but core devs have said that that's an antipattern for various reasons, e.g. see #4: https://github.com/meteor/meteor/issues/1595#issuecomment-28338105.
One last thing, the current function assumes a string array, you'd have to wrap it in code that only executes once there actually IS a string array present.
LMK what you think.
