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1 files changed, 37 insertions, 0 deletions
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+# 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
+}