bash_templates

#!/bin/bash
########################## - BASH TEMPLATES - ###############################

#_ section_variables

########## _header files_ ###########
#source ./<path/somefilename>
#source ./<path/somefilename> 

########### _variables_ #############
a1=$1; a2=$2; a3=$3; a4=$4

#_ section_functions

########### _functions_ #############

#_ section_main

############## _main_ ###############


#_ regex_comparison
#  for re or check if number
if [[ $1 =~ ^[0-9] ]]; then
        echo "$1 is an integer between 1-9"
fi

#_ missing_requirements_exit
# error function 
function error(){
         echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $*" >&2
}

# didnt supply any arguments when executing script
if [[ $# -lt 0 ]]; then
        err "Missing required argument\n"
        exit 1
fi

# did not run as root
if [[ $UID == 1 ]];then 
        err "Error: you must be root to run this script, try sudo <scriptname>"
        exit 1
fi

#_ skeleton_main_while_if
function main(){ # <arg1> <arg2>
        local input1
        local input2
        input1=$1
        input2=$2
        # infinite loop
        while :
        do
                if [[ $1 == 1 ]]; then
                        #something
                elif [[ $2 < 1 ]]; then
                        #something
                else
                        #something
                fi
        done
}

#_ skeleton_while
while :
do
        #something
done

#_ skeleton_for_loop
for i in $1
do
        #something
done

#_ skeleton_int_if_statement
if (( $num > 10 )); then
        #something
fi

#_ skeleton_if_statement
if [[ "$item" !== "" ]] || [[ "$item2" == "" ]]; then
        #something
elif [[ "$item" == "" ]]; then
        #something
else
        #something
fi

#_ skeleton_for_if_nested
for i in $item
do
        if [[ "$i" == "" ]]; then
                #something
        fi
done

#_ skeleton_if_for_nested
if [[ -n "$item" ]]; then
        for i in $item
        do
                echo "$i"
        done
fi

#_ library_of_basic_functions
function print_date(){
        date +"%D %M %Y" | awk '{print $1}'
}
pd=$(print_date)

function print_time(){
        date | awk '{print $5}' | tr ":" " " | awk '{print $1" "$2}' | tr " " ":"
}
pt=$(print_time)

function delfile(){
        local file1
        file1=$1
        if [ -f $file ]; then
                rm "$file"
        else
                printf "\n\033[31mError:\033[36m cant delete, file does not exist\033[0m\n"
        fi
}

function percentage(){
        local part
        local whole
        part=$1
        whole=$2
        echo $(( part * 100 / whole ))
}

# library_of_complex_functions


function trimstring() {
    # trim leading and trailing white space
    : "${1#"${1%%[![:space:]]*}"}"
    : "${%"${##*[![:space:]]}"}"
    printf '%s\n' "$"
}

function regex() {
    # Usage: regex "string" "regex"
    [[ $1 =~ $2 ]] && printf '%s\n' "${BASH_REMATCH[1]}"
}

function upper() {
        # change string to uppercase
        echo ${1}|tr "[[:lower:]]" "[[:upper:]]"
}

function lower() {
        # if upper to lower
        echo ${1}|tr "[[:upper:]]" "[[:lower:]]"
}

function trim_quotes() {
    # Usage: trimquotes "string"
    : "${1//'}"
    printf '%s\n' "${//"}"
}

function strip_all() {
    # Usage: stripall "string" "pattern"
    printf '%s\n' "${1//$2}" # //all, /one, instance of
}


# end