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added 9 characters in body

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edited Apr 23, 2022 at 7:40

With POSIX-ly sedly sed, you can attain the required results for both scenarios, as shown:

w='[[:alpha:]][_[:alnum:]]*'
echo 'deploy-api-productionN' | 
sed -n -e "/^\($w-\)\{0,1\}deploy-/s/^$w\(-\($w\)\)\{1,\}\$/\2/p"

Observations:

since sed has no symbol for a word, we will build a regex for that and store them in shell variable $w
\{0,11\} is BRE for ?
\{1,\} is BRE for +
$...$ is BRE for (...)

With POSIX-ly sed , you can attain the required results for both scenarios, as shown:

w='[[:alpha:]][_[:alnum:]]*'
echo 'deploy-api-productionN' | 
sed -n -e "/^\($w-\)\{0,1\}deploy-/s/^$w\(-\($w\)\)\{1,\}\$/\2/p"

Observations:

since sed has no symbol for a word, we will build a regex for that and store them in shell variable $w
{0,1} is BRE for ?
{1,} is BRE for +
(...) is BRE for (...)

With POSIX-ly sed, you can attain the required results for both scenarios, as shown:

w='[[:alpha:]][_[:alnum:]]*'
echo 'deploy-api-productionN' | 
sed -n -e "/^\($w-\)\{0,1\}deploy-/s/^$w\(-\($w\)\)\{1,\}\$/\2/p"

Observations:

since sed has no symbol for a word, we will build a regex for that and store them in shell variable $w
\{0,1\} is BRE for ?
\{1,\} is BRE for +
$...$ is BRE for (...)

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answered Apr 23, 2022 at 4:24

guest_7

With POSIX-ly sed , you can attain the required results for both scenarios, as shown:

w='[[:alpha:]][_[:alnum:]]*'
echo 'deploy-api-productionN' | 
sed -n -e "/^\($w-\)\{0,1\}deploy-/s/^$w\(-\($w\)\)\{1,\}\$/\2/p"

Observations:

since sed has no symbol for a word, we will build a regex for that and store them in shell variable $w
{0,1} is BRE for ?
{1,} is BRE for +
(...) is BRE for (...)