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# 1  
Old 03-07-2013
Regular expression, seemingly simple but
Hello,

I want to test a hour variable with an expression regular
The format is 00 01 02 03.......19 20 21 22 23
what follows in red doesn't work, it's clear 19 for example can't work.
Can you help me the right regular expression ?

Code:
case "$3" in
([0-2][0-3])
  # Nothing, OK !
  ;;
(*)
  echo 'Fatal, $3 = '"'$3'"', bad format' >&2
  #exit 1
  ;;

# 2  
Old 03-07-2013
Try it without the open bracket.

The format of a case statement (in ksh at least) is:

Code:
case $var in
   match1) Action ;;
   match2) Action ;;
   *)   Action ;;
esac

I hope that this helps.


Robin
Liverpool/Blackburn
UK
# 3  
Old 03-07-2013
Quote:
Originally Posted by amazigh42
Hello,

I want to test a hour variable with an expression regular
The format is 00 01 02 03.......19 20 21 22 23
what follows in red doesn't work, it's clear 19 for example can't work.
Can you help me the right regular expression ?

Code:
case "$3" in
([0-2][0-3])
  # Nothing, OK !
  ;;
(*)
  echo 'Fatal, $3 = '"'$3'"', bad format' >&2
  #exit 1
  ;;

To be pedantic: those patterns are not regular expressions. It's just sh pattern matching notation.

To be helpful: use multiple patterns.
Code:
case "$3" in
([01][0-9] | 2[0-3])
  # Nothing, OK !
  ;;
(*)
  echo 'Fatal, $3 = '"'$3'"', bad format' >&2
  #exit 1
  ;;

Regards,
Alister

---------- Post updated at 08:55 AM ---------- Previous update was at 08:52 AM ----------

Quote:
Originally Posted by rbatte1
Try it without the open bracket.

The format of a case statement (in ksh at least) is:

Code:
case $var in
   match1) Action ;;
   match2) Action ;;
   *)   Action ;;
esac

The opening parenthesis is typically omitted, but it is allowed, even on ksh.

Regards,
Alister
These 2 Users Gave Thanks to alister For This Post:
amazigh42 rbatte1
# 4  
Old 03-07-2013
That's me told then! Well, I'm happy to be corrected.

Robin
# 5  
Old 03-08-2013
Quote:
Originally Posted by alister
To be pedantic: those patterns are not regular expressions. It's just sh pattern matching notation.

To be helpful: use multiple patterns.
Code:
case "$3" in
([01][0-9] | 2[0-3])
  # Nothing, OK !
  ;;
(*)
  echo 'Fatal, $3 = '"'$3'"', bad format' >&2
  #exit 1
  ;;

Regards,
Alister

---------- Post updated at 08:55 AM ---------- Previous update was at 08:52 AM ----------



The opening parenthesis is typically omitted, but it is allowed, even on ksh.

Regards,
Alister
Thanks a lot Alister Smilie Super

---------- Post updated at 10:44 AM ---------- Previous update was at 04:00 AM ----------

Thanks
Last edited by amazigh42; 03-09-2013 at 01:43 AM..
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