PATH manipulation functions' library

path.sh

# PATH manipulation functions' library

# if $1 exists in $PATH then true
path_exists() {
  echo ":$PATH:" | grep -q ":$1:"
}

# remove all occurence of $1 in $PATH.
remove_path_all() {
  PATH="$(echo $PATH| sed '
    s|:'"$1"':|:|g
    s|^'"$1"':||
    s|:'"$1"'$||
    s|^'"$1"'$||
  ')"
}

# add $1 to the head of $PATH.
add_path_first() {
  PATH="$1${PATH:+:$PATH}"
}

# add $1 to the tail of $PATH.
add_path_last() {
  PATH="${PATH:+$PATH:}$1"
}

# add $1 next to the first occurence of $2 in $PATH.
add_path_next_to() {
  PATH="$(echo $PATH| sed '
    s|^'"$2"':|&'"$1"':|
    t
    s|:'"$2"':|&'"$1"':|
    t
    s|:'"$2"'$|&:'"$1"'|
    t
    s|^'"$2"'$|&:'"$1"'|
  ')"
}

# add $1 previous to the first occurence of $2 in $PATH.
add_path_previous_to() {
  PATH="$(echo $PATH| sed '
    s|^'"$2"':|'"$1"':&|
    t
    s|:'"$2"':|:'"$1"'&|
    t
    s|:'"$2"'$|:'"$1"'&|
    t
    s|^'"$2"'$|'"$1"':&|
  ')"
}