in reply to Re^3: XYZ Manipulation
in thread XYZ Manipulation
Which, seems fairly self-evident to fix, but I am unsure how to. I tried changing the parenthesis around (0 .. $#data) to [..], like the error suggested.Useless use of array element in void context at ./t2 line 30 (#1) (W void) You did something without a side effect in a context that + does nothing with the return value, such as a statement that doesn't re +turn a value from a block, or the left side of a scalar comma operator. +Very often this points not to stupidity on your part, but a failure of +Perl to parse your program the way you thought it would. For example, +you'd get this if you mixed up your C precedence with Python precedence +and said $one, $two = 1, 2; when you meant to say ($one, $two) = (1, 2); Another common error is to use ordinary parentheses to construct a + list reference when you should be using square or curly brackets, for example, if you say $array = (1,2); when you should have said $array = [1,2]; The square brackets explicitly turn a list value into a scalar val +ue, while parentheses do not. So when a parenthesized list is evaluat +ed in a scalar context, the comma is treated like C's comma operator, wh +ich throws away the left argument, which is not what you want. See perlref for more on this. This warning will not be issued for numerical constants equal to 0 + or 1 since they are often used in statements like 1 while sub_with_side_effects(); String constants that would normally evaluate to 0 or 1 are warned about. Missing argument in printf at ./t2 line 29, <IN> line 5 (#2) (W uninitialized) A printf-type format required more arguments tha +n were supplied. Use of uninitialized value in subtraction (-) at ./t2 line 38, <IN> li +ne 5 (#3) (W uninitialized) An undefined value was used as if it were alread +y defined. It was interpreted as a "" or a 0, but maybe it was a mi +stake. To suppress this warning assign a defined value to your variables. To help you figure out what was undefined, perl will try to tell y +ou the name of the variable (if any) that was undefined. In some cas +es it cannot do this, so it also tells you what operation you used th +e undefined value in. Note, however, that perl optimizes your progr +am anid the operation displayed in the warning may not necessarily ap +pear literally in your program. For example, "that $foo" is usually optimized into "that " . $foo, and the warning will refer to the concatenation (.) operator, even though there is no . in your program.
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