Your example of converting a GTK window into an IRC command is suggestive. It suggests that my mental model is mostly in terms of code that manipulates basic datatypes like strings, integers, floats, and closures, and lists/hashes/sets/etc of them, whereas you're thinking of code that manipulates more complex opaque datatypes representing higher-level constructs. It is of course possible to implement complex data in terms of simple data, but are you then doing work in your head that the compiler could be doing for you? When I'm coding in Perl, I'm thinking about what the variable contains, rather than how it's represented. "1" contains 1, albeit as a string. $cmd might contain an IRC command, hopefully represented with some nice OO interface provided by Net::IRC::Command or whatever. Passing it to a function which expects a GTK window would be fine at the time, but would cause a runtime error when the code tries to invoke an undefined method on it. Does this count as a type error? I suppose it counts as a "Does not walk like a duck" error...
When I read your comment, my first reaction would be "why would anyone try to do that?". But now I'm assuming a programmer who knows when a variable represents an IRC command (or, more generally, which implements the bit of the interface that $_ wants to use), which is effectively one who has some sort of type-checking subroutine running somewhere in $_'s head.
From man perltoot:
Some languages provide a formal syntactic interface to a class's methods, but Perl does not. It relies on you to read the documentation of each class. If you try to call an undefined method on an object, Perl won't complain, but the program will trigger an exception while it's running. Likewise, if you call a method expecting a prime number as its argument with a non-prime one instead, you can't expect the compiler to catch this. (Well, you can expect it all you like, but it's not going to happen.)
C++ functions, by the way, if handed arguments of the wrong type, will attempt to invoke constructors on their arguments to coerce them into the right types. IIRC, this only works with classes, not basic types. And I don't think it does this recursively, though that would be pretty cool :-)
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When I read your comment, my first reaction would be "why would anyone try to do that?". But now I'm assuming a programmer who knows when a variable represents an IRC command (or, more generally, which implements the bit of the interface that $_ wants to use), which is effectively one who has some sort of type-checking subroutine running somewhere in $_'s head.
From
man perltoot:C++ functions, by the way, if handed arguments of the wrong type, will attempt to invoke constructors on their arguments to coerce them into the right types. IIRC, this only works with classes, not basic types. And I don't think it does this recursively, though that would be pretty cool :-)