Meaning of <=> (less than, equal, greater than) in Perl?
From Perldoc:
Binary "<=>" returns -1, 0, or 1 depending on whether the left argument is numerically less than, equal to, or greater than the right argument. If your platform supports NaNs (not-a-numbers) as numeric values, using them with "<=>" returns undef. NaN is not "<", "==", ">", "<=" or ">=" anything (even NaN), so those 5 return false. NaN != NaN returns true, as does NaN != anything else. If your platform doesn't support NaNs then NaN is just a string with numeric value 0.
jtpereyda
Maintainer of boofuzz. "If you're going to make a backward-compatibility-breaking change, no time is better than now; things will be worse in the future." Eric Lippert Sharp Regrets: Top 10 Worst C# Features
Updated on June 05, 2022Comments
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jtpereyda almost 2 years
In this answer, I saw the syntax
<=>
; what does this mean? It seems to be some sort of comparison based on the context, but that's all I can gather. Partial context:sub rev_by_date { $b->[9] <=> $a->[9] } my @sorted_files = sort rev_by_date @files;
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jtpereyda over 12 yearsThank you, that link will be helpful too!