Page Comparison

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• If the argument is empty, the array will be sorted in ascending order using a string comparisonthe cmp operator.
• If the argument is the string "reverse", the array will be sorted in descending order using a string comparisonthe cmp operator.
• If the argument is the string "numeric", the array will be sorted in ascending order using a number comparisonthe <=> operator.
• If the argument is the string "ciremun" ("numeric" backwards), the array will be sorted in descending order using a number comparisonthe <=> operator.
• If the argument is a function, the function will be used to perform pair-wise comparisons of the members of the array for purposes of doing the sort. The function must take two arguments and return -1, 0, or 1 depending on whether the first argument is less than, equal to, or greater than the second. The <=> and cmp comparison operators are useful with sort().

Note that because the default behavior is to do a string comparison, number sorts can give unexpected results, as shown in the first example.

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