How to replace a part of variable name in a template file

Question

I am trying to write a file from a sample template file. I need to replace ONLY $UPPERINTERFACE with interface.

This is the sample template.txt

localparam $UPPERINTERFACE_WDTH = 1;
localparam $UPPERINTERFACE_DPTH = 8;
localparam $UPPERINTERFACE_WTCHD = 2;

This is the code:

from string import Template
intf = "interface"
rdfh = open("template.txt", "r").readlines()
wrfh = open("myfile.txt", "w")
for line in rdfh:
    s = Template(line)
    s = s.substitute(UPPERINTERFACE=intf.upper())
    wrfh.write(s)
rdfh.close()
wrfh.close()

Expected output:

localparam interface_WDTH = 1;
localparam interface_DPTH = 8;
localparam interface_WTCHD = 2;

As it is taking $UPPERINTERFACE_WDTH as a variable to be replaced, I am getting following error:

KeyError: 'UPPERINTERFACE_WDTH'

Is there any way I can replace only $UPPERINTERFACE with interface here?

a_guest · Accepted Answer · 2019-04-17 22:49:34Z

1

You can use curly braces {} to narrow down the template key as in following template string:

>>> line = 'localparam ${UPPERINTERFACE}_WDTH = 1;'
>>> Template(line).substitute(UPPERINTERFACE=intf.upper())
'localparam INTERFACE_WDTH = 1;'

The documentation states the following:

${identifier} is equivalent to $identifier. It is required when valid identifier characters follow the placeholder but are not part of the placeholder, such as "${noun}ification".

edited Apr 17, 2019 at 22:49

answered Apr 17, 2019 at 22:43

a_guest

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1 Comment

npatel Over a year ago

I think you have missed last line of my question. I need to replace ONLY $UPPERINTERFACE with interface.

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