tag line editing, tag key editing

sed_tagkey_in_dir.bash

#!/bin/bash

# Tag line editing
# Change the line 
#     from
#         vocabulary grammar
#     to 
#         tag:: vocabulary grammar
# Change by a given tag value such as "vocabulary" or "grammar"
# Omit the tag line if they already have the key word of "tag"
# Use the -r [extended regex pattern]
# Backup your data first if they're important

data_dir=/path/to/data

tagvalue="vocabulary"

tagline_filter="/^tag/!"
tagkey="tag:: "
filtered_operation="s/^(.*$tagvalue([[:space:]]|$))/$tagkey\1/"
sed_directive="$tagline_filter $filtered_operation"
# echo "$sed_directive"

find_cmd="find $data_dir -maxdepth 1 -type f"

for fpath in `$find_cmd`
do
    echo $fpath
    # -r for extended regex
    sed -r "$sed_directive" -i $fpath
done