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Diffstat (limited to 'examples/functions/seq2')
| -rw-r--r-- | examples/functions/seq2 | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/examples/functions/seq2 b/examples/functions/seq2 new file mode 100644 index 0000000..4a54498 --- /dev/null +++ b/examples/functions/seq2 @@ -0,0 +1,56 @@ +# +# Chet Ramey <chet.ramey@case.edu> +# +# Copyright 1998 Chester Ramey +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2, or (at your option) +# any later version. +# +# TThis program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software Foundation, +# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +# Generate a sequence from m to n, m defaults to 1. + +seq () +{ + declare -i lo hi i # makes local + local _SEQ INIT COMPARE STEP + + case "$1" in + -r) INIT='i=$hi _SEQ=""' COMPARE='let "i >= $lo"' STEP='let i-=1' ; shift ;; + *) INIT='i=$lo _SEQ=""' COMPARE='let "i <= $hi"' STEP='let i+=1' ;; + esac + + case $# in + 1) lo=1 hi="$1" ;; + 2) lo=$1 hi=$2 ;; + *) echo seq: usage: seq [-r] [low] high 1>&2 ; return 2 ;; + esac + + # equivalent to the as-yet-unimplemented + # for (( "$INIT" ; "$COMPARE" ; "$STEP" )); do _SEQ="${_SEQ}$i "; done + eval "$INIT" + while eval "$COMPARE"; do + _SEQ="${_SEQ}$i " + eval "$STEP" + done + echo "${_SEQ# }" + return 0 +} + +# like the APL `iota' function (or at least how I remember it :-) +iota() +{ + case $# in + 1) seq 1 "$1"; return $?;; + *) echo "iota: usage: iota high" 1>&2; return 2;; + esac +} |