19 lines
1.4 KiB
Rexx
19 lines
1.4 KiB
Rexx
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/*╔════════════════════════════════════════════════════════════════════╗
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║ Calling a function with optional arguments. ║
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║ ║
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║ Note that not passing an argument isn't the same as passing a null ║
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║ argument (a REXX variable whose value is length zero). ║
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╚════════════════════════════════════════════════════════════════════╝*/
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x= 12; w= x/2; y= x**2; z= x//7 /* z is x modulo seven. */
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say 'sum of w, x, y, & z=' SumIt(w,x,y,,z) /*pass five args, the 4th arg is "null"*/
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exit /*stick a fork in it, we're all done. */
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SumIt: procedure
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$= 0 /*initialize the sum to zero. */
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do j=1 for arg() /*obtain the sum of a number of args. */
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if arg(j,'E') then $= $ + arg(j) /*the Jth arg may have been omitted. */
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end /*j*/
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return $
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