在 Jinja2 中添加自定义令牌（例如 %% somevar %%）

Question

I'm making a Flask app for local development (on a Mac) of HTML templates that will eventually be served through ASP.NET.

For the purposes of local development, I want a way to replace the contents of .NET-style tokens with some data, meaning that Jinja2 would need to be able to recognize %%... %% tokens in addition to the standard ones: {{... }} , <%... %> , etc.

Everything I've found online pertains to the inclusion of some new functionality within the existing tags (eg {{ my_custom_function | arg1 arg2 }} )

But what about defining a new pattern for tags altogether? Has anyone done this successfully? And will it require modification to the Jinja2 core?

Answer 1

As far as I know, you can use one set for block_start_string and block_end_string , as well as one set for variable_start_string and variable_end_string .

From jinja2/environment.py

`block_start_string`
    The string marking the begin of a block.  Defaults to ``'{%'``.

`block_end_string`
    The string marking the end of a block.  Defaults to ``'%}'``.

`variable_start_string`
    The string marking the begin of a print statement.
    Defaults to ``'{{'``.

`variable_end_string`
    The string marking the end of a print statement.  Defaults to
    ``'}}'``.

You can override these with environment variables. Though, I don't think there is a way to have multiple types recognized. For instance, you can't have {{ and <% both work, but with a little hackery you certainly could.

Answer 2

In addition to the correct answer maybe an example implementation to change the variable marker:

Add following header to the first line in the jinja2 template file.

#jinja2:  variable_start_string: "#{" , variable_end_string: "}#"