'''[Tcl Learning Exercises]: Answer: Number Sign Class'''


** Description **

Write a procedure that takes one argument, a number, and returns `-1`, `0`, or
`1`, indicating that the number is negative, zero, or positive, respectively.
The procedure may contain exactly one command, `[expr]`, which may use the
''if-then-else'' (`?...:`) operator at most one time.  '''Bonus Round:''' Add
an additional constraint:  The ''if-then-else'' operator may not be used.

Here is one answer:

======
proc numsign n {expr {$n == 0 ? 0 : $n/abs($n)}}
======

Scroll down for the bonus round answer...
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Here is a solution by [rmax] to the bonus round:

======
proc numsign n {expr {($n > 0) - ($n < 0)}}
======


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