set -o errexit # in case caller did not have -e in #! line

if test ! "$_util_sh_include_guard_utils"; then

isset() { test "${!1+isset}"; }

realpath() { readlink -f -- "$1"; }

include_guard_var() { realpath "$1"|builtin command sed 's/[^a-zA-Z0-9_]/_/g'; }

self_not_included() # usage: if self_not_included; then ... fi

{

	test $# -ge 1 || set -- "${BASH_SOURCE[1]}"

	local include_guard="$(include_guard_var "$1")"

	alias self_being_included=false

	! isset "$include_guard" && \

	{ eval "$include_guard"=1; alias self_being_included=true; }

}

# to load newly-defined aliases for use in functions in the same file:

fi

if self_not_included "${BASH_SOURCE[0]}"; then

shopt -s expand_aliases

#### vars

#### aliases

unalias() { builtin unalias "$@" 2>&- || true; } # no error if undefined

# usage: alias alias_='var=value run_cmd '

#### functions

#### exceptions

# usage: cmd || { save_e; ...; rethrow; }

alias export_e='e=$?'

alias save_e='declare e=$?'

alias rethrow='return "$e"'

fi # load new aliases

# usage: try cmd...; ignore status; if catch status; then ...; fi; end_try

function try() { e=0; "$@" || { export_e; true; }; }

alias try='declare e; "try" ' # last space alias-expands next word

catch() { test "$e" -eq "$1"; e=0; }

ignore() { catch "$@" || true; }

alias end_try='rethrow'

fi # load new aliases

#### integers

let!() { let "$@" || true; } # always returns true; safe to use for setting

	# "If the last ARG evaluates to 0, let returns 1" (`help let`)

bool2int() { try test ! "$1"; echo "$e"; } # empty->0; non-empty->1

#### strings

repeat() # usage: str=... n=... repeat

sed_ere_flag="$(test "$(uname)" = Darwin && echo E || echo r)"

rtrim() { sed 's/[[:space:]]+$//' <<<"$1"; }

#### arrays

join() { local IFS="$delim"; echo "$*"; } # usage: delim=... join elems...

reverse() # usage: array=($(reverse args...))

{

	for (( i=$#; i > 0; i-- )); do printf '%q ' "${!i}"; done

}

contains() # usage: contains value in_array...

#### paths

canon_rel_path()

{

# makes $1 a canon_rel_path if it's a filesystem path

#### verbose output

err_fd=2 # stderr

usage() { echo "Usage: $1" >&2; return 2; }

log_fd=2 # stderr

if test "$explicit_errors_only"; then verbosity=0; fi # hide startup logging

# set verbosity

if isset verbose; then : "${verbosity:=$(bool2int "$verbose")}"; fi

if isset vb; then : "${verbosity:=$vb}"; fi

: "${verbosity=2}" # default

: "${verbosity:=0}" # ensure non-empty

export verbosity # propagate to invoked commands

: "${log_level_indent=| }" "${log_indent=}"

export log_level_indent log_indent # propagate to invoked commands

fi # load new aliases

can_log() { test "$verbosity" -gt 0; } # verbosity=0 turns off all logging

log() { if can_log; then echo "$log_indent$PS4$1" >&"$log_fd"; fi; }

# usage: symbol=... log_custom msg

log_custom()

log_err() { symbol=* verbosity=1 log_fd="$err_fd" log_custom "$@"; }

log_info() { symbol='#' log_custom "$@"; }

# usage: cmd || { save_e; log_e; ...; rethrow; }

log_e() { log_err "command exited with error $e"; }

# usage: cmd || [type=...] die msg

die() { save_e; "log_${type:-err}" "$1"; rethrow; }

### command echoing

fi # load new aliases

echo_cmd() { echo_params; }

## internal commands

.()

	cmd2rel_path; set -- . "$@"; (log++; echo_params; can_log) && indent || true

	builtin "$@"

echo_eval() { echo_params; builtin eval "$@"; }

## external commands

disable_logging() { echo_eval exec "$log_fd>/dev/null"; }

function command() # usage: [cmd_log_fd=|1|2|#] command extern_cmd...

# to view only explicitly-displayed errors: explicit_errors_only=1 script...

{

	cmd2rel_path; (echo_params; can_log) && indent || true

	(

		# the following redirections must happen in exactly this order

		if test "$cmd_log_fd"; then

		if test "$cmd_log_fd" != 2; then # fd 2 not used for logging

		exec -- "$@" # -- so cmd name not treated as `exec` option

	) || return

}

# auto-echo common external commands

# usage: func() { [minor=1] echo_func; ... }

# exit status: whether function call was echoed

{

	log++; if test "$minor"; then log++; fi

	local script="$(canon_rel_path "${BASH_SOURCE[1]}")"

	can_log

}

alias echo_func='"echo_func" "$@" && indent || true'

	log++; log++

	if can_log; then

		for var in "${@%%=*}"; do log "$(declare -p "$var")"; done

	fi

# usage: cmd1 | { pipe_delay; cmd2; }

echo_stdin() # usage: input|echo_stdin|cmd

{

	log++

	if can_log; then

		pipe_delay

		echo ----- >&"$log_fd"

	else cat

}

alias echo_stdout='echo_stdin' # usage: cmd|echo_stdout

fi # load new aliases

#### streams

fd_exists() { (: <&"$1") 2>/dev/null; }

set_fd() # usage: dest=fd dir='[<>]' src=fd [noclobber=1] set_fd

{

	echo_func

	: "${dest:?}" "${dir:?}" "${src:?}"

shadow_fd() # usage: prefix=# src=fd dir='[<>]' shadow_fd

{

	echo_func

	: "${prefix:?}" "${src:?}" "${dir:?}"

	dest="$prefix$src" noclobber=1 set_fd

}

# convention: use fd 10/11/12 for command-specific alternate stdin/stdout/stderr

set_global_fds()

# allows commands to access global stdin/stdout/stderr using fd 20/21/22

# this works even when /dev/tty isn't available

{

	log++; echo_func; log++

	local prefix=2

err_fd=22 # global stderr

# usage: explicit_errors_only=1 script...

# show only explicitly-displayed errors (which have been redirected to fd 22)

# most of the time this has the same effect as `verbosity=0 script...`,

# this option should only be used for testing the explicit error displaying

if test "$explicit_errors_only"; then disable_logging; fi

#### functions

func_exists() { declare -f "$1" >/dev/null; }

copy_func() # usage: from=... to=... copy_func

# $to must not exist. to get around the no-clobber restriction, use `unset -f`.

func_override() # usage: func_override old_name__suffix

{ from="${1%%__*}" to="$1" copy_func; }

ensure_nested_func() # usage: func__nested_func() { ensure_nested_func; ... }

#### commands

top_script="$(canon_rel_path "$0")" # outermost script

top_dir="$(dirname "$top_script")"

require_not_exists() # usage: require_not_exists file || return 0

{ test ! -e "$1" || type=info die "file "$1" already exists, skipping"; }

# auto-removes a command's output file on error (like make's .DELETE_ON_ERROR)

function to_file() # usage: stdout=... [if_not_exists=1] to_file cmd...

{

	test ! "$if_not_exists" || require_not_exists "$stdout" || return 0

	"$@" >"$stdout" || { save_e; log_e; rm "$stdout"; rethrow; }

alias to_file='"to_file" ' # last space alias-expands next word

run_args_cmd() # runs the command line args command

{

	test $? -eq 0 || return

	eval set -- "$(reverse "${BASH_ARGV[@]}")"

	test $# -ge 1 || set -- all

	echo_cmd "$top_script" "$@"; "$@"

}

fwd() # usage: subdirs=(...); fwd "$FUNCNAME" "$@"

{

	echo_func

	: "${subdirs?}"

	for subdir in "${subdirs[@]}"; do

		"$(dirname "${BASH_SOURCE[1]}")"/"$subdir"/run "$@"

	done

#### URLs

localize_url() { test _"$1" = _"$(hostname -f)" || echo "$1"; }

fi