!! +exec+ +var+ +string+
tit:hex
type:$type_both
alias:tohex
syntax:!hex ``string''
mean:Returns a new string replacing every character in ``string'' by its hexadecimal code.\
  <p>\
  In particular, the result can be used as part of a variable\
  name whatever the content of ``string'' is (as long as it is not too long).\
  </p>
