How to retrieve the value of a key in a dictionary using a variable defined in TAL?

Question

I have defined a dictionary in python:

tal:define="dic python:{'a':'1', 'b':'2'};"

I have another variable defined using tal:define called var, which is either 'a' or 'b'. I get an error when I try to do:

tal:define="foo python:dic['${var}'];"

(foo would then be '1' or '2') I get KeyError: '${var}'. I've tried dic[$var], dic[var], etc and they all don't work. How do I use a variable defined previously using tal:define as a key to a dictionary to get its value.

dic[var] should work, are you sure you define correctly 'var' ... can i see the 'var' definition ? — DonCallisto, Jan 04 '12 at 20:28
oh, geez. you're right, I remembered I tried that one and it didn't work so I've been trying some with the '$' and curly bracket combos. — JCarter, Jan 04 '12 at 20:34

score 5 · Answer 1 · answered Jan 05 '12 at 06:18

5

Path expression syntax:

tal:define="foo dic/?var"

Python expression syntax:

tal:define="foo python:dic[var]"

See Zope Book for description of ?var syntax.

answered Jan 05 '12 at 06:18

Radim Novotny

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score 0 · Accepted Answer · answered Jan 10 '12 at 15:08

0

DonCallisto's dic[var] does work

answered Jan 10 '12 at 15:08

JCarter

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How to retrieve the value of a key in a dictionary using a variable defined in TAL?

2 Answers2