Nyquist / XLISP 2.0  - 
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block
  | Type: | - | special form (fsubr) | 
  | Source: | - | xlcont.c | 
Syntax
- (block name [body ... ])
- name  - an unevaluated symbol for the block name
 body - an arbitrary number of Lisp expressions
 returns - the value of the last expression
 
Description
The 'block' special form specifies a 'named block'
construct. The last expression in 'body' will be returned by
the 'block' construct as its result unless a return
or return-from is executed within 'block'.
The return exit will exit the nearest
[inner-most] 'block'.
The return-from exit will exit
the specified 'block'.
Examples
(defun test ()
  (block outer         ; outer BLOCK
    (print "outer")
    (block inner       ; inner BLOCK
      (print "inner")
      (return-from outer "all done")
      (print "won't get here"))))
> (test)
"outer"     ; screen output of PRINT
"inner"     ; screen output of PRINT
"all done"  ; return value
See defun, print,
return-from.
See also:
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Nyquist / XLISP 2.0  - 
Contents |
Tutorials |
Examples |
Reference