Jinja2 中的变量内部变量

Question

一、总结

我无法在 Jinja2 示例中设置变量内部使用变量。

解决方案必须与Pelican兼容。

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2. MCVE

2.1. 预期行为

Any text

    Goddess Kira greatest of all time!

    Goddess Kristina greatest of all time!


Another text

    Goddess Sasha greatest of all time!

    Goddess Katya greatest of all time!

2.2. 我的尝试

• Repl.it 上的现场演示：

Any text

    Goddess Kira greatest of all time!

    Goddess Kristina greatest of all time!


Another text

    Goddess Sasha greatest of all time!

    Goddess Katya greatest of all time!

2.3. 问题

我有重复的Goddess和greatest of all time!循环的。我可以不使用重复项吗？

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3.没有帮助

3.1. 类似问题

这个、这个、这个以及许多其他Stack Overflow 问题。

3.2. 嵌套变量

例如，以下代码不起作用：

"""Jinja2 nested variables example."""
from jinja2 import Template

KIRA_BLOCK = """
{% set first_list = ['Kira', 'Kristina'] %}
Any text
{% for name in first_list %}
    Goddess {{name}} greatest of all time!
{% endfor %}
{% set second_list = ['Sasha', 'Katya'] %}
Another text
{% for name in second_list %}
    Goddess {{name}} greatest of all time!
{% endfor %}
"""

print(Template(KIRA_BLOCK).render())

我得到回溯：

"""Jinja2 nested variables example."""
from jinja2 import Template

KIRA_BLOCK = """
{% set she_greatest = 'Goddess' {{name}} 'greatest of all time!' %}
{% set first_list = ['Kira', 'Kristina'] %}
Any text
{% for name in first_list %}
    {{she_greatest}}
{% endfor %}
{% set second_list = ['Sasha', 'Katya'] %}
Another text
{% for name in second_list %}
    {{she_greatest}}
{% endfor %}
"""

print(Template(KIRA_BLOCK).render())

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4. 真实例子

为了防止XY 问题，我发布了截断的真实代码：

4.1. 预期行为

Traceback (most recent call last):
  File "KiraJinja2.py", line 18, in <module>
    print(Template(KIRA_BLOCK).render())
  File "C:\Python37\lib\site-packages\jinja2\environment.py", line 945, in __new__
    return env.from_string(source, template_class=cls)
  File "C:\Python37\lib\site-packages\jinja2\environment.py", line 880, in from_string
    return cls.from_code(self, self.compile(source), globals, None)
  File "C:\Python37\lib\site-packages\jinja2\environment.py", line 591, in compile
    self.handle_exception(exc_info, source_hint=source_hint)
  File "C:\Python37\lib\site-packages\jinja2\environment.py", line 780, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "C:\Python37\lib\site-packages\jinja2\_compat.py", line 37, in reraise
    raise value.with_traceback(tb)
  File "<unknown>", line 2, in template
  File "C:\Python37\lib\site-packages\jinja2\environment.py", line 497, in _parse
    return Parser(self, source, name, encode_filename(filename)).parse()
  File "C:\Python37\lib\site-packages\jinja2\parser.py", line 901, in parse
    result = nodes.Template(self.subparse(), lineno=1)
  File "C:\Python37\lib\site-packages\jinja2\parser.py", line 888, in subparse
    self.stream.expect('block_end')
  File "C:\Python37\lib\site-packages\jinja2\lexer.py", line 384, in expect
    self.name, self.filename)
jinja2.exceptions.TemplateSyntaxError: expected token 'end of statement block', got '{'

该示例显示了 static 的位置和变量的位置。

4.2. 我的尝试

• Repl.it 上的现场演示：

<div class="KiraCategory">First</div>

    <a onclick="KiraFunction(document.all.sitename.value, 'https://Alpha.com');" class="Foo">Alpha</a>

    <a onclick="KiraFunction(document.all.sitename.value, 'https://Bravo.ru');" class="Bar">Beta</a>


<div class="KiraCategory">Second</div>

    <a onclick="KiraFunction(document.all.sitename.value, 'https://Charlie.net');" class="Baz">Gamma</a>

我的尝试重复。

Answer 1

您正在寻找Jinja宏；调用时产生输出的函数：

{% macro she_greatest(name) -%}
    Goddess {{name}} greatest of all time!
{%- endmacro %}

{% set first_list = ['Kira', 'Kristina'] %}
Any text
{% for name in first_list %}
    {{ she_greatest(name) }}
{% endfor %}
{% set second_list = ['Sasha', 'Katya'] %}
Another text
{% for name in second_list %}
    {{ she_greatest(name) }}
{% endfor %}

演示：

>>> from jinja2 import Template
>>> demo = '''
... {% macro she_greatest(name) -%}
...     Goddess {{name}} greatest of all time!
... {%- endmacro %}
...
... {% set first_list = ['Kira', 'Kristina'] %}
... Any text
... {% for name in first_list %}
...     {{ she_greatest(name) }}
... {% endfor %}
... {% set second_list = ['Sasha', 'Katya'] %}
... Another text
... {% for name in second_list %}
...     {{ she_greatest(name) }}
... {% endfor %}
... '''
>>> print(Template(demo).render())




Any text

    Goddess Kira greatest of all time!

    Goddess Kristina greatest of all time!


Another text

    Goddess Sasha greatest of all time!

    Goddess Katya greatest of all time!

或者，将其应用到您的现实生活示例中：

>>> from jinja2 import Template
>>> demo = '''
... {% macro she_greatest(name) -%}
...     Goddess {{name}} greatest of all time!
... {%- endmacro %}
...
... {% set first_list = ['Kira', 'Kristina'] %}
... Any text
... {% for name in first_list %}
...     {{ she_greatest(name) }}
... {% endfor %}
... {% set second_list = ['Sasha', 'Katya'] %}
... Another text
... {% for name in second_list %}
...     {{ she_greatest(name) }}
... {% endfor %}
... '''
>>> print(Template(demo).render())




Any text

    Goddess Kira greatest of all time!

    Goddess Kristina greatest of all time!


Another text

    Goddess Sasha greatest of all time!

    Goddess Katya greatest of all time!