[Python-Dev] Improve error message "UnboundLocalError: local variable referenced before assignment"
tjreedy at udel.edu
Thu Nov 1 02:20:01 CET 2012
On 10/31/2012 4:28 PM, R. David Murray wrote:
>"local variable referenced before assignment" *is*
> a pointer to the concept of when global variables become local...perhaps
> there is a better wording, do you have a suggestion?
The current wording is an exact, concise, description of the problem.
Rather than tinkering with the wording, I think a more general solution
might be a new HOWTO: Understanding exception messages. It could have
alphabetically sorted entries for exceptions and messages that people
local variable referenced before assignment
Problem: You used a local name 'x' in an expression before you assigned
it a value. So the interpreter could not compute the value of the
expression. Remember that assignment makes a name local unless it is
declared global or nonlocal.
Remedy: If you intend 'x' to refer to a glocal or nonlocal name, add the
necessary global or nonlocal declaration. If you intend
Terry Jan Reedy
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