This repository contains various helper functions for awk.

To use them, either include whole thing in your program or run awk like below. Every function in this repository is POSIX-compatible.

awk -f awk++ -f myscript.awk /etc/passwd

Functions:

• strtonum(str, base) - converts string from base X to base 10 - just like gawk specific option, except with base argument. If base isn't specified, heurestics are used to detect it (if it starts with 0x then it is base 16, if it starts with 0 then it is base 8, base 10 (useless) otherwise.
• numtostr(number, base) - exact reverse of strtonum, it converts base 10 number to other base.
• ceil(number) - ceils number. Note that there is no floor function (int works exactly like it).
• ord(character) - converts character to number. As this information isn't publicly available in awk, when this function will be used for first time, the table of characters will be created.
• chr(number) - converts character to its number, just like ord() except reverse.
• reverse(string) - reverses string.
• len(array) - gets length of array.
• empty(array) - empties array (just like delete in gawk, except it's not implementation-specific).
• push(array, value) - pushes value to array.
• pop(array) - pops value from array.
• shift(array) - shifts value from array.
• unshift(array, value) - unshifts value from array.
• clone(return, array) - clones array.
• join(array, separator) - joins array by separator.
• slice(return, array, start, end) - slices array, start is first array element, end is last array element. Negative values mean counting from end.
• first(array) - returns first array element (identical to array[1]).
• first(return, array, n) - returns first n array elements.
• initial(return, array, n) - doesn't return last n elements.
• last(array) - returns last array element
• last(return, array, n) - returns last n array elements.
• rest(return, array, n) - doesn't return first n elements.
• compact(return, array) - returns array without falsy values.
• contains(array, value) - returns first position of value.
• difference(return, array, without) - array difference.
• intersection(return, array, with) - values in both array and with arrays.
• union(ret, array1, array2) - join two arrays.
• unique(ret, array) - returns unique array elements.
• flip(ret, array) - reverses array.