Bash metaprogramming

bash_metaprogramming.sh

#!/bin/bash

# list all custom BASH functions
lsf() {
	if [[ ! -d ~/.bash_functions ]] ; then
		if [[ ! -f ~/.bashrc ]] ; then
			echo "lsf: err: no such directory ~/.bash_functions, no such file ~/.bashrc"
			return 1
		fi

		while IFS='' read -r LINE || [[ -n $LINE ]] ; do
			LET=`echo $LINE | fold -w1`
			CHARS=`echo $LET | tr -d '\040\011\012\015'`

			if [[ ( "${CHARS[*]: -1}" == "{" ) && ( "${CHARS: -2:1}" == ")" && "${CHARS: -3:1}" == "(" ) ]] ; then
				LEN=${#CHARS}
				LEN="$(( $LEN - 1 ))"
				echo "${CHARS:0:$LEN}"
			fi
		done < ~/.bashrc
	else
		for FILE in ~/.bash_functions/* ; do
			PARTS=( ${FILE//./ } )
			if [[ "${PARTS[*]: -1}" == "sh" ]] ; then
				echo "`basename ${FILE:0:${#FILE}-3}`()"
			fi
		done
	fi
}

# make a BASH function out of the last x commands
makef() {
	fc -rnl > /dev/null 2>&1
	if [[ $? -ne 0 ]] ; then 
		echo "makef: err: history is empty"
		return 1
	fi

	if [[ $# -eq 0 ]] ; then
		NUM=1
		RANDO=`random 5`
		NAME="function_$RANDO"
	elif [[ $# -eq 1 ]] ; then
		NUM=$1
		RANDO=`random 5`
		NAME="function_$RANDO"
	elif [[ $# -eq 2 ]] ; then
		NUM=$1
		NAME=$2
		RANDO=`random 5`
	else
		echo "makef: err: incorrect number of arguments"
		return 1
	fi

	[ -n "$NUM" ] && [ "$NUM" -eq "$NUM" ] 2>/dev/null
	if [ $? -ne 0 ]; then
		echo "makef: err: first argument must be a number"
		return 1
	fi
	if [[ $NUM -lt 1 ]] ; then
		echo "makef: err: first argument must be a positive integer"
		return 1
	fi

	NAMESTR=( $NAME )
	if [[ ${#NAMESTR[@]} -gt 1 ]] ; then
		echo "makef: err: name of function cannot contain spaces"
		return 1
	fi

	if [[ ! -d ~/.bash_functions ]] ; then
		SOURCE=~/.bashrc
	else
		if [[ ! -f ~/.bash_functions/$NAME.sh ]] ; then
			SOURCE=~/.bash_functions/$NAME.sh
		else
			echo "makef: err: ~/.bash_functions/$NAME.sh already exists"
			return 1
		fi
	fi

	NUM=$(( $NUM + 1 ))

	printf "\n" >> $SOURCE
	printf "$NAME() {\n" >> $SOURCE
	fc -rnl | head -$NUM > $RANDO
	tac $RANDO > .tempfile

	INDEX=0
	while IFS='' read -r CMD || [[ -n "$CMD" ]] ; do
		if [ $INDEX -eq 0 ] ; then
			INDEX+=1
			continue
		fi
		printf "$CMD\n" >> $SOURCE
	done < ".tempfile"

	printf "}\n" >> $SOURCE

	rm -rf .tempfile
	rm -rf $RANDO
	source $SOURCE
}

# make a shell script out of the last x commands
makes() {
	fc -rnl > /dev/null 2>&1
	if [[ $? -ne 0 ]] ; then 
		echo "makes: err: history is empty"
		return 1
	fi

	if [[ $# -eq 0 ]] ; then
		NUM=1
		NAME="script.sh"
	elif [[ $# -eq 1 ]] ; then
		NUM=$1
		NAME="script.sh"
	elif [[ $# -eq 2 ]] ; then
		NUM=$1
		NAME=$2
	else
		echo "makes: err: incorrect number of arguments"
		return 1
	fi

	[ -n "$NUM" ] && [ "$NUM" -eq "$NUM" ] 2>/dev/null
	if [ $? -ne 0 ]; then
		echo "makes: err: first argument must be a number"
		return 1
	fi
	if [[ $NUM -lt 1 ]] ; then
		echo "makes: err: first argument must be a positive integer"
		return 1
	fi

	NAMESTR=( $NAME )
	if [[ ${#NAMESTR[@]} -gt 1 ]] ; then
		echo "makes: err: name of function cannot contain spaces"
		return 1
	fi

	RANDO=`random`
	fc -rnl | head -$NUM > $RANDO
	tac $RANDO > $NAME
	rm -rf $RANDO
}

# remove a BASH Function by name
rmf() {
	if [[ $# -ne 1 ]] ; then
		echo "rmf: err: incorrect number of arguments"
		return 1
	fi

	if [[ "${1: -2:2}" == "()" ]] ; then
		FUNCTION="${1:0:-2}"
	else
		FUNCTION="$1"
	fi

	if [[ -d ~/.bash_functions ]] ; then
		FILENAME="$FUNCTION.sh"
		if [[ ! -f ~/.bash_functions/$FILENAME ]] ; then
			echo "rmf: err: $FUNCTION.sh not found in ~/.bash_functions"
			return 1
		fi
		rm -rf ~/.bash_functions/$FILENAME
	else
		if [[ ! -f ~/.bashrc ]] ; then
			echo "rmf: err: no such directory ~/.bash_functions, no such file ~/.bashrc"
			return 1
		fi

		RANDO=`random`
		TITLE="$FUNCTION() {"
		EDIT=0
		FOUND=0
		COUNT=0
		while IFS='' read -r LINE || [[ -n "$LINE" ]] ; do
			if [[ "$TITLE" == "$LINE" ]] && [[ $EDIT -eq 0 ]] ; then
				EDIT=1
				FOUND=1
			elif [[ "$LINE" == "}" ]] && [[ $EDIT -eq 1 ]] ; then
				EDIT=0
				COUNT="$(( $COUNT + 1 ))"
			else
				if [[ $EDIT -eq 0 ]] ; then
					printf "%s\n" "$LINE" >> $RANDO
				fi
			fi
		done < ~/.bashrc

		cat $RANDO > ~/.bashrc
		rm -rf $RANDO
		if [[ $FOUND -eq 0 ]] ; then
			echo "rmf: err: $FUNCTION not found in ~/.bashrc"
			return 1
		else
			if [ $COUNT -eq 1 ] ; then
				echo "Removed $FUNCTION from ~/.bashrc"
				source ~/.bashrc
			else
				echo "Removed $FUNCTION $COUNT times from ~/.bashrc"
				source ~/.bashrc
			fi
		fi
	fi
}