rc/sh/days

#!/usr/bin/env sh
# YES_ZSH
# YES_BASH
# YES_DASH

days() { ### @-
    ### compute days since a given date.
    ###
    ### ```
    ### $ days 'January 1 1970'
    ### 18838
    ### ```
    [ $# -le 1 ] || { printf "%s\n" "$0: too many arguments" >&2; return 1; }
    echo $(( ($(date +%s) - $(date -d "$1" +%s)) / 60 / 60 / 24 ))
}

[ "${SOURCING:-0}" -gt 0 ] || days "$@"
first pass over sh: improve compatibility, fix stuff 2021-07-29 05:44:12 -07:00			`#!/usr/bin/env sh`
overhaul 2021-07-29 00:37:35 -07:00			`# YES_ZSH`
first pass over sh: improve compatibility, fix stuff 2021-07-29 05:44:12 -07:00			`# YES_BASH`
			`# YES_DASH`
overhaul 2021-07-29 00:37:35 -07:00
add and restore some docstrings 2021-07-30 17:57:08 -07:00			`days() { ### @-`
			`### compute days since a given date.`
			`###`
			### ```
			`### $ days 'January 1 1970'`
			`### 18838`
			### ```
overhaul 2021-07-29 00:37:35 -07:00			`[ $# -le 1 ] \|\| { printf "%s\n" "$0: too many arguments" >&2; return 1; }`
			`echo $(( ($(date +%s) - $(date -d "$1" +%s)) / 60 / 60 / 24 ))`
			`}`

			`[ "${SOURCING:-0}" -gt 0 ] \|\| days "$@"`