javascript - In Meteor using #each, check if 'last' element in the collection reached - Stack Overflow

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I'm iterating through a collection in Meteor using {{#each}} and I would like to know if I'm in the last element, as I can do in AngularJS while using ngRepeat with $last.

It could be used, for example to construct human readable enumerations like 'I like cats, dogs and dolphins' :

Template.myTemplate.helpers({
    likedAnimals: function(){return ['dogs','cats','dolphins'];}
});

<template name='myTemplate'>
    I like  
    {{#each likedAnimals}}
        {{#if !$first && !$last}}, {{/if}}
        {{#if $last}} and {{/if}}
        {{this}}
    {{/each}}
</template>

Is there any way to check this condition in Meteor?

I'm iterating through a collection in Meteor using {{#each}} and I would like to know if I'm in the last element, as I can do in AngularJS while using ngRepeat with $last.

It could be used, for example to construct human readable enumerations like 'I like cats, dogs and dolphins' :

Template.myTemplate.helpers({
    likedAnimals: function(){return ['dogs','cats','dolphins'];}
});

<template name='myTemplate'>
    I like  
    {{#each likedAnimals}}
        {{#if !$first && !$last}}, {{/if}}
        {{#if $last}} and {{/if}}
        {{this}}
    {{/each}}
</template>

Is there any way to check this condition in Meteor?

• javascript
• meteor
• meteor-blaze
• spacebars

Share Improve this question Follow edited Nov 16, 2014 at 15:47 Gerard Carbó asked Nov 11, 2014 at 10:09 Gerard CarbóGerard Carbó 1,9051919 silver badges1717 bronze badges 2

• @Р̀СТȢѸ́ФХѾЦЧШЩЪЫЬѢѤЮѦѪѨѬѠѺѮѰѲѴ, can you please change your username to something less obnoxious? – Dan Dascalescu Commented Nov 11, 2014 at 20:27
• 2 That's a good question. – Mitar Commented Nov 14, 2014 at 20:39

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 8

If any of you are wondering how to do the same with collection cursors, there's a much simpler way thanks to handlebar-helpers package.

You could then use:

$mapped - will map $first, $last, and $index onto your cursor or array

bined with $last helper in your template like that:

{{#each $mapped myCursor}}
  {{name}}{{#unless $last}},{{/unless}}
{{/each}}

PS: this also works with arrays

Using underscore.js :

Template.registerHelper('last',
    function(list, elem) {
        return _.last(list) === elem;
    }
);

<template name='myTemplate'>
    {{#each likedAnimals}}
        {{#if last ../likedAnimals this}} I'm the last ! {{/if}}
    {{/each}}
</template>

Worked with a reactive data source for me with meteor 1.1.0.1 (I don't know when Template.parentData() was introduced in meteor).

This isn't supported in meteor yet (version 1.0), but you can kind of add it yourself by doing something like this:

Template.myTemplate.helpers({
    likedAnimals: function(){
        var animals = ['dogs','cats','dolphins']
        return animals.map(function(animal, index){
            return {
                name: animal,
                isFirst: index==0,
                isLast: index==animals.length-1
            }
        })
    }
})

However, this does not play nice with reactivity (making it work properly with reactivity is much harder, which I guess is the reason why this isn't a built in feature yet), but if you return a simple array that's not dependent on any reactive data source, this should work fine.

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