Issue with VERBATIM blocks being defined after NEURON block with THREADSAFE

[iomaganaris]

Translation of mod files with VERBATIM blocks defined after a NEURON block with THREADSAFE keyword fail with the same error as without having the THREADSAFE keyword, complaining about thread safety of the mod file.
Moving the NEURON block with the THREADSAFE keyword before the VERBATIM block, for example in the beginning of the mod file, fixes the issue.
Example mod file: https://github.com/suny-downstate-medical-center/M1/blob/master/mod/ch_CavL.mod

[nrnhines]

There was an intention at the beginning that BLOCK order does not matter. However I think there are several situations now that that is not the case. Probably mostly where usage preceded declaration. In fact, I think THREADSAFE really has to appear early in the NEURON block in some cases. It would be tedious to fix all this in mod2c and/or nocmodl and I don't think it is too onerous to require the NEURON block to be first. I expect for nmodl it is trivial to support the original intention as that creates the AST prior to any subtantive processing.

[pramodk]

@nrnhines: I was discussing this with @iomaganaris. There are (quite) some mod files where VERBATIM blocks comes before NEURON block and adding THREADSAFE doesn’t help. We saw these mod files while working with Salvador.

For above specific case, I thought we can see if it’s “easy” to keep/update some flag about if THREADSAFE specified or not.

You are right that it’s tedious to fix this for all possible cases without having something like AST. But I was planning to take a quick look and see if most common/obvious case we saw with netpyne models can be fixed.

This was just to make more mod files compatible with coreneuron, without need of manual mod file changes.