Identifying white space in a twig variable - php

Question

I have a situation where I need to identify if there is a blank space in a variable in a twig template, and to treat it slightly differently.
Given names in this application are stored with middle initials in the given name field; they are not stored separately.
What I'm trying to achieve is this: Typically most given names are one word, e.g. "John" or "Susan" or something similar. In some of these cases we have cases where the middle initial is stored within this variable (e.g. John J)
Following standard citation standards, we need to be able to list items like this:
{{ surname }}, {{ given_name }}, ed.
This way it would appear like "Smith, John, ed." This is normally fine, however in some situations, where there is a middle initial, it appears as "Smith, John J, ed." - this is incorrect. I can't add a period after the given name, as "Smith, John., ed" would be an incorrect citation standard.
What I'm trying to do is to identify if a given_name contains a space, followed by a single letter, and then format it differently.
Something like this:
{% if given_name [has a blank space preceding a single letter] %}
{{ given_name }}., ed.
{% else %}
{{ given_name }}, ed.
{% endif %}
Is there a way to do this with regex within twig, or is there another method?
Thanks in advance

Answer 1

We can translate your requirement:
has a blank space preceding a single letter
In this little algorithm:
{% set given_name = 'John J' %}
{% set given_name_elems = given_name|split(' ') %}
{% set size = given_name_elems|length %}
{% if size >0 and given_name_elems[size-1]|length == 1%}
{ given_name }}., ed.
{%else%}
{{ given_name }}, ed.
{%endif%}
I suggest you to incapsulate this logic in a function or in a macro.
You could made some try in this working example

Answer 2

This is possible, but is not necessarily going to handle edge cases well. Assuming that you need to do the whole thing in twig, you could do something like this:
{% set nameArray = given_name | split(' ') %}
{% set first_name = nameArray[0] %}
{% set middle_initial = nameArray[1] is defined ? " "~nameArray[1]~"." : ""%}
At this point `middle_initial is now set to either an empty string or the middle initial with the period so you can output the full name like:
{{ surname }}, {{first_name ~ middle_initial}}, ed

Answer 3

You could use a regex with the matches comparison operator and add the dot if given_name matches the pattern.
{{ given_name }}{% if given_name matches '/^.+ .$/' %}.{% endif %}

Answer 4

Sorry, I didn't give you a good answer initially. I've updated my code and my twigfiddle. It's a bit simpler than #Matteo 's:
{% set given_name = 'John J' %}
{% set nameArray = given_name|split(' ') %}
{% if nameArray[1] is defined %}
{{ nameArray[0] }} {{ nameArray[1] }}., ed.
{% else %}
{{ nameArray[0] }}, ed.
{% endif %}
Where {{ nameArray[0] }} specifies the first element of the array. If nameArray1 contains anything, then it is defined.
Here is a working twigfiddle to show you it works.