[SOLVED] convert text to snake case to camelCase in MAC OS High sierra

Issue

I would like to convert 2+ words to camel case. I tried in online ubuntu version and it works. But not on mac os.

my amazing-long_variable -> myAmazingLongVariable

echo "my amazing-long_variable" | sed -E 's/[ |_|-]([a-z])/\U\1/gi' | sed -E 's/^([A-Z])/\l\1/'

My Output:

sed: 1: "s/[ |_|-]([a-z])/\U\1/gi": bad flag in substitute command: 'i'

2nd attempt:

echo "my amazing-long_variable" | sed -E 's/[ |_|-]([a-z])/\U\1/g' | sed -E 's/^([A-Z])/\l\1/'

Output:

myUamazingUlongUvariable

Thanks

Solution

\U and \l are GNU sed extensions. Perl will work for you out of the box:

echo "my amazing-long_variable" | perl -nE 'say lcfirst join "", map {ucfirst lc} split /[^[:alnum:]]+/'

You read this from right to left

• split /[^[:alnum:]]+/ splits the default variable $_ (i.e., the current line) on any sequence of non-alphanumeric characters, resulting in the list "my", "amazing", "long", "variable"
• map {ucfirst lc} applies the code ucfirst lc to each word in turn.
  • as you might guess, lc lower cases the word, then ucfirst capitalizes the first character
  • this results in the list "My", "Amazing", "Long", "Variable"
• join "", joins the words using the empty string: "MyAmazingLongVariable"
• lcfirst lower cases the first character: "myAmazingLongVariable"

The perl option -n loops over the input file and/or standard input, putting each line in the "default variable" $_. -l takes care of handling the line endings for the print command.

Answered By - glenn jackman