toggle x-ray

is there a mel command i can use to toggle x-ray shading in the selected viewport?... or perhaps specify a camera in the syntax and continue to use it (perp for example)....
please send any additional info with response posts... i would like to use the opportunity as a learning step... as well as a workaround. thanks

http://www.highend3d.com/boards/showflat.p...;o=0&fpart=

look at this and see if it helps.

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