expert help sought [offtopic]

[Helmut Jarausch <jarausch@xxxxxxxxxxxxxxxxxxx>]

Hi,

please help.
I am desparately in need for help on the following piece of
code within a 'configure' file.
It's run under '/bin/sh' which is a symlink to '/bin/bash'
but I known that real experts are reading this mailing list.

The following code fails in the 2nd line with 
syntax error near unexpected token `('
../htmlwidget2/configure: line 4957: `  case `(ac_space=' '; set | grep ac_space) 2>&1` in'

here are the lines 4956 ff

(set) 2>&1 |
  case `(ac_space=' '; set | grep ac_space) 2>&1` in
  *ac_space=\ *)
    # `set' does not quote correctly, so add quotes (double-quote substitution
    # turns \\\\ into \\, and sed turns \\ into \).
    sed -n \
      -e "s/'/'\\\\''/g" \
      -e "s/^\\([a-zA-Z0-9_]*_cv_[a-zA-Z0-9_]*\\)=\\(.*\\)/\\1=\${\\1='\\2'}/p"
    ;;
  *)
    # `set' quotes correctly as required by POSIX, so do not add quotes.
    sed -n -e 's/^\([a-zA-Z0-9_]*_cv_[a-zA-Z0-9_]*\)=\(.*\)/\1=${\1=\2}/p'
    ;;
  esac >> confcache

I admit I don't really understand what's going on and even what's meant
to be going on.

Many thanks for your help,

Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany