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Convert a script to one-liner

Terminal - Convert a script to one-liner
(sed 's/#.*//g'|sed '/^ *$/d'|tr '\n' ';'|xargs echo) < script.sh
2013-10-26 23:23:51
User: knoppix5
Functions: sed tr xargs
Convert a script to one-liner


Convert an one-liner to script:

foo() { <one-liner> ; }


typeset -f foo


unset -f foo


There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

What a fascinating idea :-)

Unfortunately, it's easily confused.

Many compound statements get unnecessary semi-colons:

if [ "$x" = 1 ]; then; echo one; fi

Also, one of my favourite shell variables gets chewed up: $# (the number of parameters).

Comment by flatcap 76 weeks and 6 days ago

slightly improoved, yet far from perfect:

(sed '/if *$\|then *$\|else *$/!s/$/;/g'|sed 's/^#.*;\| #.*;//g'|xargs echo) <script.sh
Comment by knoppix5 76 weeks and 5 days ago

I ended up with:

(sed -e 's/^\s*\(.*\)\s*/\1/' -e 's/\([^$]\|^\)#.*//' -e '/^$/d' | paste -s -d\; | sed -e 's/\<\(then\|do\)\>;/\1 /g') < script.sh

sed part 1: trim leading/trailing whitespace

sed part 2: # at the beginning of a line, or # (but not preceded by $)

sed part 3: delete empty lines

paste: join lines with a ;

sed part 4: replace 'then;' or 'do;' with 'then' or 'do'

However, your 'xargs echo' is much nicer.

(sed -e 's/\([^$]\|^\)#.*//' -e '/^$/d' | tr '\n' ';' | xargs echo | sed -e 's/\<\(then\|do\)\>;/\1/g') < script.sh
Comment by flatcap 76 weeks and 5 days ago

Your point of view

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