title: Validation Pattern MUMPS
body: <p>I am working to create a program in M that reads an input of names in a certain format. Once the user places a null value it prints out all of the values. Where I am getting stuck is reading into a global variable. I look forward to any input I can receive.</p>
  
  <pre><code>          n prompt,val,done
            s prompt="Enter a name (LAST,FIRST MI): "
            s val="" f in=1:1 s val=$O(^ZNAME(val)) q:val=""
            f  w !,prompt r val q:val=""  d   q:done 
            . i val'?1.A1",".1" "1.A.1(1" "1A) w !,"Invalid name" q
            . s val=$GET(^ZNAME)
            . s done=1
            i val="" q  
            w !,"You entered: ",val
           . s done=1
           q
  </code></pre>