Interesting Ruby (MRI anyway) has command line options to make it act pretty similar to awk:
-n adds an implicit "while gets ... end" loop. "-p" does the same but prints the contents of $_ at the end. "-e" lets you put an expression on the command line. "-F" specified the field separator like for awk. "-a" turns on auto-split mode when you use it with -n or -p, which basically adds an implicit "$F = $_.split to the while gets .. end loops.
So "ruby -[p or n]a -F[some separator] -e ' [expression gets run once every loop]'" is good for tasks that are suitable for "awk-like" processing but where you may need access to other functionality than what awk provides..
You probably know it, but in case not, and for others who might not know: Ruby was influenced by Perl, and Perl was influenced by awk. (Both Ruby and Perl were influenced by other languages too.) And (relevant to this thread) Perl was influenced by C, sed, and Unix shell too.
-n adds an implicit "while gets ... end" loop. "-p" does the same but prints the contents of $_ at the end. "-e" lets you put an expression on the command line. "-F" specified the field separator like for awk. "-a" turns on auto-split mode when you use it with -n or -p, which basically adds an implicit "$F = $_.split to the while gets .. end loops.
So "ruby -[p or n]a -F[some separator] -e ' [expression gets run once every loop]'" is good for tasks that are suitable for "awk-like" processing but where you may need access to other functionality than what awk provides..