Can we use hyphens with liquid

[rajpratyush]

I was rendering a page built with jekyll and liquid and it throwed an error.

here is the html code snippet
<header class="intro-header" style="background-image: url('{{ site.baseurl }}/{% if page.header-img %}{{ page.header-img }}{% else %}{{ site.header-img }}{% endif %}');">
<div class="container">
<div class="row">
<div class="col-lg-8 col-lg-offset-2 col-md-10 col-md-offset-1">
<div class="post-heading" style="padding: 30px 0">
<h1>{{ page.title }}</h1>
{% if page.subtitle %}
<h2 class="subheading">{{ page.subtitle }}</h2>
{% endif %}
<span class="meta">Posted by {{ page.author }} on {{ page.date | date: "%B %-d, %Y" }}</span>
</div>
</div>
</div>
</div>
</head>

here is the error message:

my config.yml has:
liquid:
error_mode: strict
strict_variables: true
strict_filters: true

further there is some more error messages that I get are :
[:dot, "."] is not a valid expression in "{{ .spec.host }}"

this was the error message when my config_.yml had

liquid:
error_mode: warn

is it a valid expression??

[dylanahsmith]

Hyphens are allowed in variables. E.g.

irb> Liquid::Template.parse('{% assign a-b = "value" %} {{ a-b }}', error_mode: :strict).render
=> " value"

I think the header-img error you are getting is because of #1034.

The leading . in {{ .spec.host }} doesn't look valid though. Why do you have it there?

It does look like we are missing documentation for what is allowed in a variable name.

[rajpratyush]

actually the site that was build is unable to render header and footer if you want i can give you the link of the file. so i used strict variables so that i can find where the error is and debug it.

[sebastienros]

Also, looks like {{ assign [var] = [value] }} is more permissive than {{ [var] }}, for instance this will work even with error_mode: :strict

{% assign $@!$/b = 3 %}{{ b }}

[dylanahsmith]

Also, looks like {{ assign [var] = [value] }} is more permissive than {{ [var] }},

Yeah, strict parsing hasn't been added to the assign tag yet.

[dylanahsmith]

Looks like this issue is actually a duplicate of #1034, where {% if page.header-img %} is used to check for the presence of the property which results in an error when it doesn't exist and strict_variables is used.

This isn't an issue with hyphens for variables, which does seem to be supported, which can be seen by the variable name in the error message