Mercury shell script

mmi

#!/bin/sh

if [ $# -eq 0 ]; then
    exit 1 # the first argument *MUST* be the executed script
fi
if [ -x $1 ]; then
    SHELL_SCRIPT=$(basename $0)
    SCRIPT=$1
    mv -f $SCRIPT ${SCRIPT}.tmp
    shift
    MODULE=$(basename $SCRIPT .m)
    TARGET_FILE=${MODULE}.m
    DIR=$(dirname $SCRIPT)
    echo "% automatically generated from: $SCRIPT">$DIR/$TARGET_FILE
    echo ":- module ${MODULE}.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is cc_multi.
:- implementation.
'\$0' = \"$SCRIPT\".
'\$dp0' = \"$DIR\".
'\$#' = $#.
'\$pwd' = \"$PWD\".
:- import_module list,string, enum, float, math, int, dir, maybe.
:- pragma source_file(\"${MODULE}.m\").
#2">>$DIR/$TARGET_FILE
    tail -n +2 ${SCRIPT}.tmp | \
        sed 's/^main\((!IO)\)\?\s*:-/main(!IO) :- command_line_arguments(Args, !IO),/'>>$DIR/$TARGET_FILE
    cd $DIR
    MCFLAGS="--infer-all --no-inform-inferred --make --use-grade-subdirs"
    (  mmc $MCFLAGS -- $MODULE 2>/dev/null && \
       mv -f ${SCRIPT}.tmp ${SCRIPT} && \
       exec ./${MODULE} $*
    ) || ( ([ -r ${SCRIPT}.tmp ] && mv -f ${SCRIPT}.tmp ${SCRIPT} || true ) && \
	       cat ${MODULE}.err )
    rm ${MODULE}.err
else
    exit 2
fi

test.m

#!/usr/bin/env mmi

square(X) = Square :- int.pow(X, 2, Square).

main(!IO) :-
    Number = (if Args = [A0 | _] then det_to_int(A0) else 2),
    print("args    =  ", !IO), write_list(Args, ",", write, !IO), nl(!IO),
    format("square(%d) = %d\n",     [i(Number), i(square(Number))], !IO),
    format("sloc    = \"%s:%d\"\n", [s($file), i($line)], !IO),
    format("$module = \"%s\"\n", [s($module)], !IO),
    format("$file   = \"%s\"\n", [s($file)], !IO),
    format("$grade  = \"%s\"\n", [s($grade)], !IO),
    format("$0      = \"%s\"\n", [s('$0')], !IO),
    format("$pwd    = \"%s\"\n", [s('$pwd')], !IO),
    format("$dp0    = \"%s\"\n", [s('$dp0')], !IO),
    format("$#      = %d\n",  [i('$#')], !IO).