Re: [Help-glpk] Where with an assignment to a constraint in GLPK/L

[Andrew Makhorin]

Thank you very much for your bug report.

>Is it a purpose that 
>
>FLOW_BALANCE[k,i] where true := sum(j, X[k,j,i]);
>
>fails with an assertion error? It is allowed according to the grammar
>description (Modeling Language GLPK/L, v3.2, 5.1 Assignment Statement)

Surely it is not a purpose, it is a bug. The construction you used is
syntactically correct, and the bug appears due to an internal logical
error in the language interpreter.

I will fix the bug in the next release. However, if you need the bug to
be fixed in the current version (glpk 3.2.1), please inform me, and I'll
send you a patched version of the file 'glplan7.c'.

Andrew Makhorin