source Matrix -- source of a map

source Matrix -- source of a map

Synopsis:

Function: source -- source of a map

Input:

an instance of class Matrix.

Code:

     -- ../m2/methods.m2:184-187
     source Thing := (h) -> (
          if h#?(symbol source) then h.source
          else if (class h)#?(symbol source) then (class h)#?(symbol source)
          else error ( toString h, " of class ", toString class h, " has no source" ))