Python string formatting: For loops?

Question

I really enjoy the Django/Jinja style of formatting. I understand wanting to keep logic and presentation separate, but the if statements and for loops are ideal when reporting a changing amount of data.

I am creating a "Report" class that returns some information about the inputs and outputs of a function in a more verbose way, and what I would like is to have a string like:

template="""
INPUTS:
{{% for key,value in inputsdict.items() %}}
  {{key}}: {{value}}
{{% endfor #}}

OUTPUTS:
{{% for key,value in outputsdict.items() %}}
  {{key}}: {{value}}
{{% endfor #}}
"""

and then I could just call a classic template.format(**kwargs)

I am wondering if Jinja is my best bet to do this, or whether python has a native, lightweight string loop formatting functionality of some kind that I should be looking at.

Edit: Additionally, if Jinja is my best bet, I would really appreciate an example of how to use it outside of a web-oriented environment. The docs are kind of hard to navigate.

Answer 1

Generate your data from your for loops and then put them in the results.

There's no need to over-use the format template system. Just use it for the pieces where it's needed.

inputs  = ['%s: %s' % (k, v) for k, v in input_dict.items()]
outputs = ['%s: %s' % (k, v) for k, v in output_dict.items()]
print '\n'.join('INPUTS:',  '\n  '.join(inputs),
                '', 
                'OUTPUTS:', '\n  '.join(outputs)) 

You could make the inputs/outputs creation step a function, or use something from the json library for pretty printing.