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Comment by morphir | Hacker News Reader

3> (define x (lambda (y) (* 2 y))) * WARNING -- defining global variable: x 3> x Bus error

Gambit v4.5.2 OSX 10.5

Of course, I do know that x should not be evaluated. For that have to type (x 3). But its still annoying, and very unnecessary. In DrScheme/PLT I get a: > x #<procedure:x> Explicitly telling me its a procedure.

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I've reproduced your crash. The issue is that you're using define within a nested REPL, which isn't supported [1].

However, a segfault is really not acceptable. I'll file a report for this.

[1] http://www.iro.umontreal.ca/~gambit/doc/gambit-c.html#Debugg...

Relevant section: "Note that some special forms (define in particular) can only be evaluated in the global interaction environment."

I'm fairly sure that the nested repl 'define' being allowed at all is a fairly recent change, I seem to recall just getting an error when trying to define in a nested repl in 4.4.x.

Right, it looks like a regression in 4.5.*. 4.4.4 is fine.

This is fixed in 4.5.3.

The crash was caused by printing the value of the procedure in the nested REPL. Using define in nested REPLs works, but you'll get a warning about it.

I've had these crashes, and I can tell you exactly what it is that is causing it...

You're not at the top level of the repl, for some reason, defining things at a lower nesting level of the repl sometimes produces crashes, it's annoying yes, but it's not a huge disaster :)

if you use ",t" to get back to the top level after an error, you shouldn't see those crashes.

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