Quick bash slugify

quick-slugify.sh

echo "$STRING" | iconv -t ascii//TRANSLIT | sed -r s/[^a-zA-Z0-9]+/-/g | sed -r s/^-+\|-+$//g | tr A-Z a-z

Best to replace tr A-Z a-z at the end by tr "[:upper:]" "[:lower:]" to support accentuated characters like É f.i.

Best to replace tr A-Z a-z at the end by tr "[:upper:]" "[:lower:]" to support accentuated characters like É f.i.

These characters are handled by iconv. I thought, were they not, they would be handled by sed replace, but at least in GNU sed 4.8 most of them belongs to a-z range.

╰─➤  echo É | iconv -t ascii//TRANSLIT                                                                     
E

# not every diacritic is contained in a-z
╰─➤  echo "ā, ä, ǟ, ḑ, ē, ī, ļ, ņ, ō, ȯ, ȱ, õ, ȭ, ŗ, š, ț, ū, ž." | sed -r 's/[^a-zA-Z0-9]+/-/g' | sed -r 's/^-+\|-+$//g' | tr A-Z a-z                  130 ↵
ā-ä-ǟ-ḑ-ē-ī-ļ-ņ-ō-ȯ-ȱ-õ-ȭ-ŗ-š-ț-ū-

It's good to replace multiple sed processes with a single one using multiple -e parameters.

It's good to use [:alnum:] instead of [^a-zA-Z0-9].

It's good to use tr "[:upper:]" "[:lower:]" instead of tr A-Z a-z as a matter of principle for the goal of lowercasing input. To know that tr A-Z a-z is good enough requires verifying what comes before in the pipeline, and knowing how iconv works. That's added mental burden.

Putting it together:

iconv -t ascii//TRANSLIT | sed -E -e 's/[^[:alnum:]]+/-/g' -e 's/^-+|-+$//g' | tr '[:upper:]' '[:lower:]'