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Does it have anything comparable to Lisp macros ?

Io ~= Self. It should be looked at as an Smalltalk dialect.

When one says "imperative", one hardly means "an smalltalk influenced, pure object oriented language", but more like a statically-typed Algol variant, usually a derivative of C, Fortran, Pascal or Ada.

I don't think the Io counter-example is valid, just as an Icon counter-example would be valid (yes, Icon is "imperative", but it's also an Snobol derivative with goal-oriented execution, generators and perl-like text processing prowess :-)

If someone with a functional programming background says "imperative", it usually includes all the Algol descendants and their cousins like Simula, Java, C++, Smalltalk, Python, Ruby etc. because they don't add much to the game, they are all structured around mutable state. They just put fancier labels on the same dirty stuff.

You just spoke of Smalltalk in that trollish tone. Hope you're happy.

Io has runtime macros. Messages are evaluated by the receiver and which can do whatever it wants with the message arguments (evaluate them, tear them apart and create new messages ... etc)

list(1, 2, 3, 4) select(isEven) map(+(1)) ==> list(3, 5)

isEven and +(1) are messages that select and map evaluate.

Also see:

http://hackety.org/2008/01/05/ioHasAVeryCleanMirror.html

Reader macros?

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