Bare hashes cause confusing error message in scripts

[sjamaan]

As pointed out by erkin on IRC, when you run a script with -ss which contains something like #, the error message you get is confusing, especially if you don't know about csi's history references (especially given that this is a script, not manual input).

The error is:

Error: history entry index out of range: 0

If this is the result of running a long script that somewhere contains # (or just #0), this doesn't point to the location of the issue either.

Proposed possible improvements:

• Add the # to the error message so it's clear that this syntax is causing it, even if you don't know what a "history index" is. But note that just adding it is not going to be enough, since just # also triggers this error.
• Give a better/different error when reading a bare #
• Include the line number (part of a larger issue in evaluated script code, and the hardest to implement)
• Disable history syntax when running with -s or -ss.

[sjamaan]

For reference, Chibi gives a better error: ERROR on line 57 of file op.scm: invalid char following '#': #\space

Some other Schemes have shitty error messages too, but that shouldn't stop us from improving ours ;)

erkin actually had (# . foo) in a quoted alist, not remembering that # is special syntax.

[Kooda]

Fixed in 42f3ff1bd63f563d3fd9c3329f0c5f9fc4f5b749