Reference array from key in for loop with Twig - php

In Twig I am trying to iterate over a potentially incomplete array using a fixed-length for loop so I can show what values are empty.
In PHP this would be simplified to:
for($i =0; $i <= $limit; $i++) {
if($data[$i]) {
echo $data[$i];
}
)
The only thing is that in Twig I am having problems using the key (index) of the loop to reference a value in an array, this is what I've tried and expected to work, but doesn't:
{% for i in range(0, limit-1) %}
{{ data.i }}
{% endfor %}
I could obviously use array_pad() to pad out my array in my controller, but surely there must be a way to do this in twig?

How about this:
{% for i in range(0, limit-1) %}
{% if data[i] is defined %}
{{ data[i] }}
{% endif %}
{% endfor %}

Related

converting a php line to twig [duplicate]

I'm working on a template and I need to check if something is an array. How do I do that in Twig?
I've tried
{% if my_var is iterable %}
{% for v in my_var %}
...
{% endfor %}
{% else %}
{{ my_var }}
{% endif %}
but it always prints my_var, even when my_var is really an array, as evidenced when it prints out
Array
Array
myusername
../data/table.sqlite3
Another way :
{% if my_var.count()>1 %}
If you don't want to create a custom filter use iterable, as per the docs :
iterable checks if a variable is an array or a traversable object
{% if myVar is iterable %} ... {% endif %}
Just add a custom filter:
$twig->addFilter('is_array', new \Twig_Filter_Function('is_array'));
Then use it like this:
{% if my_var|is_array %}

"While" and "repeat" loops in Twig

Are there any nice ways to use while and repeat loops in Twig? It is such a simple task, but without macros I can't find anything nice and simple.
At least do an infinite cycle and then break it in a condition?
EDIT:
I mean something like
do {
// loop code
} while (condition)
or
while (condition) {
// loop code
}
Edit 2:
Looks like it is not supported natively by twig same reason as it is not supported neither continue; or break; statements.
https://github.com/twigphp/Twig/issues/654
You can emulate it with for ... in ... if by using a sufficiently-high loop limit (10000?)
while
PHP:
$precondition = true;
while ($precondition) {
$precondition = false;
}
Twig:
{% set precondition = true %}
{% for i in 0..10000 if precondition %}
{% set precondition = false %}
{% endfor %}
do while
PHP:
do {
$condition = false;
} while ($condition)
Twig:
{% set condition = true %} {# you still need this to enter the loop#}
{% for i in 0..10000 if condition %}
{% set condition = false %}
{% endfor %}
I was able to implement a simple for loop in twig. So the following php statement:
for ($x = 0; $x <= 10; $x++) {
echo "The number is: $x <br>";
}
when translated to twig is:
{% for i in 0..10 %}
* {{ i }}
{% endfor %}
It's not a while loop but a potential workaround. The best suggestion is to leave business logic like this out of the template layer.
In a nutshell: no. This functionality implies advanced logic, which should be in your business logic, not in the template layer. It's a prime example of the separation of concerns in MVC.
Twig supports for-loops completely, which should suffice if you code correctly - being that complex conditional decisions on which data to display are taken in the business logic where they belong, which then pass a resulting array 'ready to render' to the templates. Twig then supports all nice features only needed for rendering.
This is possible, but a little bit complicated.
You can use {% include ... %} to process nested arrays, which from the comments I read is what you need to do.
Consider the following code:
nested_array_display.html
<ul>
{% for key, val in arr %}
<li>
{{ key }}:
{% if val is iterable %}
{% include 'nested_array_display.html' %}
{% else %}
{{ val }}
{% endif %}
</li>
{% endfor %}
</ul>
Warning with the top solution with "high loop limit" : the loop doesn't break when the condition returns false, it just doesn't enter the loop. So the loop runs up to the high indice

Loop till the value of variable is not zero

I have been stuck at this for a while now. I am new to twig and i am trying to iterate a code untill my variable becomes zero. I have tried this:
{% set total = 5%}
{% set i=1 %}
{% for total %}
{{i}}
{%set i=i+1%}
{% set total = total -1%}
{% endfor %}
and this
{% set i=1 %}
{% for total > 1%}
{{i}}
{%set i=i+1%}
{% set total = total - 1%}
{% endfor %}
but none are working.. What am i doing wrong?
Twig fors are more akin to PHP's foreachs (they are for iterating over a traversable). To achieve what you are describing you would do:
{% set nums = range(1, 5) %}
{% for num in nums|reverse %}
{{ num }}
{% endfor %}
In practice, you could set nums from your controller logic. Also note from the Twig manual:
Unlike in PHP, it's not possible to break or continue in a loop.
You can, however, skip elements with if. Manual example:
{% for user in users if user.active %}

Is there any way to get average values from an array when using a Twig template?

Is there any way of getting the average value of an array of value just inside a Twig template when using Symfony2?
I tried something like the following code but it doesn't work
{% set sumratings = 0 %}
{% set count = 0 %}
{% for rating in article.ratings %}
{% set sumratings = sumratings + rating.value %}
{% endfor %}
AVG: {{ sumratings / article.ratings.count }}
Any idea?
I think this should do it
{% set sumratings = 0 %}
{% for rating in article.ratings %}
{% set sumratings = sumratings + rating.value %}
{% endfor %}
AVG: {{ sumratings / article.ratings|length }}
Assuming rating.value is an integer
There is no built-in way to do that. Creating your own twig extension that can do it is simple! You need to create a filter, which is very well doumented in the cookbook: How to write a custom Twig Extension.
The answer is correct but horrible to use, right ?
It's simple:
function arrayAverage($array)
{
if (!is_array($array)) return false;
if (!count($array)) return 0;
$avg=0;
foreach ($array as $num) $avg+=$num;
$avg/=count($array);
return $avg;
}
$twig->addFilter('arrayAverage', new Twig_Filter_Function('arrayAverage'));
Now you can just do like this in your twig templates:
{{ somearray | arrayAverage }}
{{ somearray | arrayAverage | number_format }}
In modern Twig versions, there's a reduce() filter that can simplify this work, a bit:
{% set myValues = [1, 2, 3, 4, 5] %}
{% set average = (myValues | reduce((sum, val) => sum + val, 0)) / (myValues | length) %}
{{ average }} {# 3 #}
See this fiddle!

Setting element of array from Twig

How can I set member of an already existing array from Twig?
I tried doing it next way:
{% set arr['element'] = 'value' %}
but I got the following error:
Unexpected token "punctuation" of value "[" ("end of statement block"
expected) in ...
There is no nice way to do this in Twig. It is, however, possible by using the merge filter:
{% set arr = arr|merge({'element': 'value'}) %}
If element is a variable, surround it with brackets:
{% set arr = arr|merge({(element): 'value'}) %}
I ran into this problem but was trying to create integer indexes instead of associative index like 'element'.
You need to protect your index key with () using the merge filter as well:
{% set arr = arr|merge({ (loop.index0): 'value'}) %}
You can now add custom index key like ('element'~loop.index0)
If initialization only need:
{% set items = { 'apple': 'fruit', 'orange': 'fruit', 'peugeot': 'unknown' } %}
I have tried #LivaX 's answer but it does not work , merging an array where keys are numeric wont work ( https://github.com/twigphp/Twig/issues/789 ).
That will work only when keys are strings
What I did is recreate another array ( temp) from the initial array (t) and make the keys a string , for example :
{% for key , value in t%}
{% set temp= temp|merge({(key~'_'):value}) %}
{% endfor %}
t keys : 0 , 1 , 2 ..
temp keys : 0_, 1_ , 2_ ....
You can also use the following syntax:
{% set myArray = myArray + myArray2 %}
Just use this like {% set arr={'key':'value'} %} (with no blank space after the :), it works well.
But when I use it inside a for loop, to make it an array, it does not work outside of the for scope.
{% for group in user.groups %}
{% set foo={'loop.index0':'group.id'} %}
{% set title={'loop.index0':'group.title'} %}
{{ title }} //it work
{% else %}
{% set foo={'0':'-1'} %}
{% set title={'0':'未分组'} %}
{% endfor %}
{{ title }} //it does not work, saying title is not defined
{% set links = {} %}
{# Use our array to wrap up our links. #}
{% for item in items %}
{% set links = links|merge({ (loop.index0) : {'url': item.content['#url'].getUri(), 'text': item.content['#title']} }) %}
{% endfor %}
{%
set linkList = {
'title': label,
'links': links
}
%}
{% include '<to twig file>/link-list.twig'%}
Thanks for this thread -- I was also able to create an array with (loop.index0) and send to twig.
I've found this issue very annoying, and my solution is perhaps orthodox and not inline with the Twig philosophy, but I developed the following:
$function = new Twig_Function('set_element', function ($data, $key, $value) {
// Assign value to $data[$key]
if (!is_array($data)) {
return $data;
}
$data[$key] = $value;
return $data;
});
$twig->addFunction($function);
that can be used as follows:
{% set arr = set_element(arr, 'element', 'value') %}
Adding my answer in case anyone needs to update the array when merge doesn't work because it just appends to the end of an array instead of providing the ability to change an existing value.
Let's say you have an array words_array like below:
Object {
0: "First word"
1: "Second word"
2: "Third word"
}
In order to update "Second word", you can do the following:
{% set words_array = {(1): 'New word'} + words_array %}
The resulting array would be:
Object {
0: "First word"
1: "New word"
2: "Third word"
}
You can take it one step further if you are using a loop and use the loop.index0 variable something like the following:
{% for word in words_array %}
{% if word == 'Second word' %}
{% set words_array = {(loop.index0): 'New word'} + words_array %}
{% endif %}
{% endfor %}
You can declare the array as follows
{% set arr = [{'element1': 'value1','element2' : 'value2'},{'element1': 'value1','element2' : 'value2'},{'element1': 'value1','element2' : 'value2'}] %}
I had a multi dimension array. The only solution I could find out is create a new temporary array and update/add the information, which was further passed on to another twig function.
I had this problem sometime ago. Imagine you have an array like this one:
data = {
'user': 'admin',
'password': 'admin1234',
'role': 'admin',
'group': 'root',
'profile': 'admin',
'control': 'all',
'level': 1,
'session': '#DFSFASADASD02',
'pre_oa': 'PRE-OA',
'hepa_oa': 'HEPA-OA',
'pre_ra': 'HEPA-RA',
'hepa_ra': 'HEPA-RA',
'deodor_ra': 'DEODOR-RA'
}
So, you want to show this data in two rows, but remove the password from that list. To this end, split in 2 arrays will be easy with the slice filter. However, we have to remove the password. For that reason, I'm using this snippet. The idea is to put all the elements lesser than the data elements size divided by 2. To calculate this we use the filter length. Now to get the index of the current element we user loop.index. And finally we *push an associative element in the left or right array. An associative array has two components key and value. To reference an array key in twit we operator () and we use the merge filter to push into the array as shown here {% set left_list = left_list|merge({ (key): value }) %}
This is the complete solution.
{% set left_list = {} %}
{% set right_list = {} %}
{% set limit = data|length // 2 %}
{% for key, value in data|cast_to_array %}
{% if key != 'password' %}
{% if loop.index <= limit %}
{% set left_list = left_list|merge({ (key): value }) %}
{% else %}
{% set right_list = right_list|merge({ (key): value }) %}
{% endif %}
{% endif %}
{% endfor %}
{% for key, value in left_list %}
<p>
<label for="{{key}}">{{key}}</label>
<input type="text" name="{{key}}" id="{{key}}" value="{{value}}"
class="text ui-widget-content ui-corner-all">
</p>
{% endfor %}

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