cd-alias-add bash command

gistfile1.txt

ALIAS_FILE_CDS=~/.bash_aliases_cd
function _funct_cd_alias_add
{
    local name=$1
    name=$(echo $name | sed s/^cd-//) # remove any leading cd- (we'll add that)
    local varname=$(echo $name | sed s/-/_/g) # replace minus with underscore
    shift

    local directory=$* # can't do replace on $* value directly -- man bash for more
    if [ "$directory" == "" ]; then
       directory=$(pwd)
    fi
    directory="${directory// /\\ }" # replace all spaces with slash-space

    # remove (comment out) any existing alias with the same name
    local tmpfile="/tmp/alias-file-$$-${RANDOM}"
    rm -f $tmpfile
    cat $ALIAS_FILE_CDS | sed s"/^alias cd-${name}=/#alias cd-${name}=/"g | \
                          sed s"/^export CD_${varname}=/#export CD_${varname}=/"g > $tmpfile
    if [ -s $tmpfile ]; then # if tmpfile is greater than zero size
      chgrp staff $tmpfile # this is a Apple thing .. otherwise move complains about the group
      mv -f $tmpfile $ALIAS_FILE_CDS
    fi
    rm -f $tmpfile

    # add alias and create alias for the current shell
    local cd_cmd="alias cd-$name=\"pushd $directory\""
    local cd_exp="export CD_${varname}=${directory}/"
    echo "export CD_${varname}=${directory}/" >> $ALIAS_FILE_CDS
    echo "alias cd-$name=\"pushd $directory\" ## `date`" >> $ALIAS_FILE_CDS
    eval $cd_cmd
    eval $cd_exp
}
alias cd-alias-add=_funct_cd_alias_add