topaz hum 8-) | Code :
 - ${parameter/pattern/string}
 -        ${parameter//pattern/string}
 -               The pattern is expanded to produce a pattern just as in pathname expansion.  Parameter is
 -               expanded  and the longest match of pattern against its value is replaced with string.  In
 -               the first form, only the first match is replaced.  The second form causes all matches  of
 -               pattern  to  be  replaced  with  string.   If pattern begins with #, it must match at the
 -               beginning of the expanded value of parameter.  If pattern begins with %, it must match at
 -               the  end  of  the expanded value of parameter.  If string is null, matches of pattern are
 -               deleted and the / following pattern may be omitted.  If parameter is @ or *, the  substi-
 -               tution  operation  is  applied to each positional parameter in turn, and the expansion is
 -               the resultant list.  If parameter is an array variable subscripted with @ or *, the  sub-
 -               stitution  operation is applied to each member of the array in turn, and the expansion is
 -               the resultant list.
 
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   un truc dans le genre (man bash ...)    |