Title: Merging in case primitive
Goal: Merge all instances of the expression `{reply, X*Data+2}'.
Parameters:
    [   {file,"ref_case1v3.erl"},
        {posrange,{144,160}},
        {varname,"B"} ].
Documentation:
 The expression can be substituted,
 as the variable `X' is bound before the case expression,
 and the expressions `X=1' and `X=2' in the case branches are pattern matchings.
