This is an excellent point — that Ruby embodies the syntactic insight that most functions that take any functional argument take only one functional argument.

This is an excellent point — that Ruby embodies the syntactic insight that most functions that take any functional argument take only one functional argument. Frankly this turned me off from Ruby when Matz presented it at LL2 in 2002. My reaction was “this is an ugly hack that won't work with more than one funarg, by someone who doesn't really understand functional programming”. [I was coming from years of hardcore programming in Smalltalk and Common Lisp.] It was only years later that I realized this special case was so overwhelmingly the common case that it was reasonable to give it a nice syntax, and that there's a (big) place for programming that isn't in a “functional” style, but still makes liberally use of funargs. (Most Smalltalk and Lisp that I've seen occupies this middle ground too.) It reminds me of my first reaction to Python: “Meaningful indentation is a terrible idea!” Only a year or two later when I was writing Lisp pseudocode in a notebook [late '90's — no parenthesis highlighting or syntax-directed editor on my analog notepad] did I realize that what I was sketching used whitespace as shorthand, and was practically Python as it stood. That Ruby blocks have a weird scope, and that the syntax for creating and invoking closures outside of the block syntax is so cluttered, are unfortunate and seem mostly independent of having a compact notation for single-funarg function calls. Except that if, like Lisp and Smalltalk, all use of closures used the same syntax, this syntax would probably have become more polished.