/^\s*declare\s+/ and err 'arrays/declare not portable';
/^\s*[^#]\s*which\s/ and err 'which is not portable (please use type)';
/\btest\s+[^=]*==/ and err '"test a == b" is not portable (please use =)';
+ /\bwc -l.*"\s*=/ and err '`"$(wc -l)"` is not portable (please use test_line_count)';
/\bexport\s+[A-Za-z0-9_]*=/ and err '"export FOO=bar" is not portable (please use FOO=bar && export FOO)';
# this resets our $. for each file
close ARGV if eof;