if(n)                        Tcl ( )                        if(n)



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     NAME
          if - Execute scripts conditionally

     SYNOPSIS
          if expr1 ?then? body1 elseif expr2 ?then? body2  elseif  ...
          ?else? ?bodyN?
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     DESCRIPTION
          The if command evaluates expr1 as an expression (in the same
          way  that  expr  evaluates  its argument).  The value of the
          expression must be a boolean (a numeric value,  where  0  is  |
          false  and  anything is true, or a string value such as true  |
          or yes for true and false or no for false); if  it  is  true
          then body1 is executed by passing it to the Tcl interpreter.
          Otherwise expr2 is evaluated as an expression and if  it  is
          true  then  body2  is  executed,  and so on.  If none of the
          expressions evaluates to true then bodyN is  executed.   The
          then and else arguments are optional ``noise words'' to make
          the command easier to read.  There  may  be  any  number  of
          elseif  clauses,  including zero.  BodyN may also be omitted
          as long as else is omitted too.  The return value  from  the
          command  is the result of the body script that was executed,
          or an empty string if none of the expressions  was  non-zero
          and there was no bodyN.


     KEYWORDS
          boolean, conditional, else, false, if, true























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