"CS 1520 Fall 1996 This handout demonstrates some looping 
 messages in Smalltalk and shows how the same thing can be
 done in many different ways (some very short). "

| data ctr letters |
data := Prompter prompt: 'Enter your name' default:''.
ctr := 1.
letters := 0.
[ctr <= data size]                   "Finds # of letters in a string"
   whileTrue: [                      "input by the user.  The three"
       (data at: ctr) isLetter       "implementations below do the"
          ifTrue: [ letters := letters + 1 ].    "exact same thing."
       ctr := ctr + 1.
   ].
letters printNl.              

data := Prompter prompt: 'Enter your name' default:''.
letters := 0.
data do: [ :c |  c isLetter
          ifTrue: [ letters := letters + 1 ].
     ].
letters printNl.             

letters := 0.
(Prompter prompt: 'Enter your name' default:'')
             do: [ :c | c isLetter ifTrue: [ letters := letters + 1 ]. 
             ].       
letters printNl.

((Prompter prompt: 'Enter your name' default:'') 
                    select: [ :c | c isLetter ]) printNl size printNl.!