Info Catalog eintr: Loops & Recursion eintr: dolist dotimes

eintr: while

 
 11.1 ‘while’
 ============
 
 The ‘while’ special form tests whether the value returned by evaluating
 its first argument is true or false.  This is similar to what the Lisp
 interpreter does with an ‘if’; what the interpreter does next, however,
 is different.
 
    In a ‘while’ expression, if the value returned by evaluating the
 first argument is false, the Lisp interpreter skips the rest of the
 expression (the “body” of the expression) and does not evaluate it.
 However, if the value is true, the Lisp interpreter evaluates the body
 of the expression and then again tests whether the first argument to
 ‘while’ is true or false.  If the value returned by evaluating the first
 argument is again true, the Lisp interpreter again evaluates the body of
 the expression.
 
    The template for a ‘while’ expression looks like this:
 
      (while TRUE-OR-FALSE-TEST
        BODY...)
 

Menu

 
· Looping with while          Repeat so long as test returns true.
· Loop Example                A ‘while’ loop that uses a list.
· print-elements-of-list      Uses ‘while’, ‘car’, ‘cdr’.
· Incrementing Loop           A loop with an incrementing counter.
· Incrementing Loop Details
· Decrementing Loop           A loop with a decrementing counter.
 

Info Catalog eintr: Loops & Recursion eintr: dolist dotimes