Numeric Comparisons 101 - if

Like most languages, Tcl supports an if command. The syntax is: if expr1 ?

then? body1 elseif expr2 ?

then? body2 elseif ... ?

else? ?

bodyN? The words then and else are optional, although generally then is left out and else is used.

The test expression following if should return a value that can be interpreted as representing "true" or "false": If the test expression returns a string "yes"/"no" or "true"/"false", the case of the return is not checked. True/FALSE or YeS/nO are legitimate returns.

If...