My message was approximately as follows (I realize that cloning down and grepping is always an alternative):

Searching code states explicitly that "You can't use the following wildcard characters as part of your search query: . , : ; / \ ` ' " = * ! ? # $ & + ^ | ~ < > ( ) { } [ ]. The search will simply ignore these symbols". Is it in any way possible to get around that in code search? If not, I recommend that this be placed in the backlog.

Response from James Dennes:

Thanks for the feedback on GitHub Search. It's not currently possible, but I'll add a +1 to this suggestion on our internal Feature Request List. We can't promise if we may add something like this, but we appreciate the feedback.