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> It's almost necessary for any dialect of LISP to support lambdas (i.e. functions) that contain a LISP 'do' [1] which lets you group statements.

> [1] http://www.lispworks.com/documentation/lw60/CLHS/Body/m_do_d...

'do' in most Lisps and Schemes is essentially an extended for loop, not a blocking construct. Of course, you could write

    (do ((once nil t)) ; Scheme: (do ((once #f #t))
        (once)
      (thing-1)
      (thing-2)
      ...)
or something, but that's silly.

The blocking construct is in CL called PROGN and in Scheme called begin. Lambdas in CL get what's called an "implicit PROGN" around their bodies, so you can put however many forms you want inside and the value of the last is returned. It works the same in modern Scheme lambdas.

Calling PROGN/begin "do" is solely a Clojureism as far as I know.



> Calling PROGN/begin "do" is solely a Clojureism as far as I know.

Also an ANSI-CL-LOOP-ism:

   (loop for x in '(1 2 3) do (print x) (print x))
   1
   1
   2
   2
   3
   3
Omit the do and you have a syntax error.


You would have a syntax error with a single PRINT form and no DO, too.




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