##### http://autoconf-archive.cryp.to/ax_prog_tcl.html
#
# SYNOPSIS
#
#   AX_PROG_TCL([min-version])
#
# DESCRIPTION
#
#   Searches for tcl (tclsh and wish) in PATH and checks which version
#   is installed. The macro bails out if either tcl is not found or the
#   minimum version is not satisfied, unless minimum version is "0".
#
#   Example:
#
#    AX_PROG_TCL
#
#   This checks for tcl and if not found, exits with an error. If
#   found, it prints tcl path and version number.
#
#    AX_PROG_TCL([8.0])
#
#   Checks for tcl and exits with an error if its not found or the
#   version is below 8.0.
#
# LAST MODIFICATION
#
#   2006-10-18
#
# COPYLEFT
#
#   Copyright (c) 2006 David Cluytens
#   Copyright (c) 2006 Uwe Mayer <merkosh@hadiko.de>
#
#   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 of the
#   License, or (at your option) any later version.
#
#   This 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.
#
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AC_DEFUN([AX_PROG_TCL], [
#-- check for tclsh in PATH
AC_PATH_PROG([TCLSH], [tclsh], [no])
if [(test x"$TCLSH" == x"no") && (test x"$1" != x"0")]; then
        AC_MSG_ERROR([tclsh not found])
fi

#-- check for wish in PATH
AC_PATH_PROG([WISH], [wish], [no])

#-- check vor tcl version
AC_MSG_CHECKING([tcl version])
version=`echo "puts [[set tcl_version]]" | tclsh -`
AC_MSG_RESULT([$version])

#-- compare tcl version with min-version
required=$1
if [(test x"$1" != x"") && (test "${required/./}" -gt "${version/./}")]; then
        AC_MSG_ERROR([tcl version $1 required])
fi
])dnl