Template renderer does not parse numeric variables

[antonio@…]

Currently a Variable is defined, according to the django template ​manual, as :

Variable names consist of any combination of alphanumeric characters and the underscore ("_").

If a variable is composed of numbers only, it will not get its context data correctly, coming across as an int. This patch assigns the appropriate context data to the Variable class when it encounters an integer.

Here's the current behavior:

from django.template.base import Template
from django.template.base import Context
t = Template("{{ 123 }}")
t.render(Context())

u'123'

t = Template("{{ foo }}")
t.render(Context({"foo":"bar"}))

u'bar'

[antonio@…]

Patch to assign context to numeric Variables in Django templating

[anonymous]

Definitely not full fix, it does cause regressions elsewhere - namely the view loading a changelist in the Admin.

[Simon Charette]

The issue is valid but IMHO the code should be fixed to disallow such uses of number variables and the documentation fixed accordingly (e.g Variable name can't start with an integer).

I know this might be backward incompatible but I can't see any valid use case for this behavior, looks more like a side effect/oversight of the access by index feature. Am I missing something here?

[Deepak]

I totally agree with charettes that there may not be an use case for this. Hence, I'd propose to add warning first and then raise an exceptions if integer or float variable names are used. Does it makes sense?

[anonymous]

Makes more sense as a doc ticket, agreed! Thanks for looking!

Antonio

[Tim McCurrach]

I have created a PR to update the docs. Given it will now be documented, adding in any checks or warnings seems like overkill to me.

[Jacob Walls]

​PR

[GitHub <noreply@…>]

In 7587139d:

Fixed #20423 -- Doc'd that DTL variable names may not be a number.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 7e6e8221:

[3.2.x] Fixed #20423 -- Doc'd that DTL variable names may not be a number.

Backport of 7587139d35b630a19fdc55a5f3789475e5ed26c8 from master