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read-special
Version: 4.2.1

A readable-snip<%> object is treated specially by the port generated by open-input-text-editor. When a readable-snip<%> object is encountered for the input stream, its read-special method is called to generate the read result for the snip.

(send a-readable-snip read-special source    
  line    
  column    
  position)  any/c
  source : any/c
  line : (or/c exact-nonnegative-integer? false/c)
  column : (or/c exact-nonnegative-integer? false/c)
  position : (or/c exact-nonnegative-integer? false/c)
The arguments are the same as the arguments to a procedure returned by a custom input port’s read; see Custom Ports for details. The result is also the same as the result from a read-produced procedure.