How to change a variable outside of a for loop? Scoping Issues

[tjoyce]

This question is extremely common; How do I use a counter in a variable that was created outside of a for loop. @Jsum did a good job answering that question here. I just wanted to expand on it and make this post more "searchable" by users trying to accomplish the same thing. 

{# create the counter #}
{% set counter = {'value': 1} %}

{# create a macro that will change the counter, when called #}
{% macro incrementDecrementCounter(valuechange) %}
  {% set changingCounter = counter.update({'value': counter.value + valuechange}) %}
{% endmacro %}

{# the for...loop #}
{% for n in range(10) %}
  {% if n % 3 == 0 %}
    
    {# call the macro to update the counter #}
    {{incrementDecrementCounter(-1)}}
  {% else %}

    {# call the macro to update the counter #}
    {{incrementDecrementCounter(1)}}
  {% endif %}
  <p>The loop index is: {{n}}, while the counter is: {{counter.value}}</p>
{% endfor %}

@Anton, @dennisedson, @Stephanie-OG

[gotohubspot]

If you will use an array ( SizeLimitingPyList: [] ) rather than object ( SizeLimitingPyMap: {} ) it would be accessible in for loop.

[mIIwaukee]

Thanks everyone, here's a non-array approach.

{% set thisClient = {'name': 'none' } %}
{% for client in dynamic_page_hubdb_row.client %}
{% do thisClient.update({'name': client.name }) %}
{% endfor %}

{{thisClient.name}}

[matt_scott]

I didn't think of using a macro, that's a nice solution!

I found a hacky way to do something similar but different
This was some code I used to build a dictionary:
The ‘.append’ function actually appends to the global dictionary ‘vars’, the variable inside the set is irrelevant but is needed for the hubl to run

{% set vars = [] %}
{% for item in group %}
    {% set thisVariableDoesntDoAnything = vars.append(item.variable) %}
{% endfor %}

[matt_scott]

Since writting the above I found the "do" function and hubspot have now added the "do" function to the docs so the code doesn't seem so hacky

{% set vars = [] %}
{% for item in group %}
    {% do vars.append(item.variable) %}
{% endfor %}

[jennysowyrda · Accepted solution]

Thanks for sharing @tjoyce!