39.9 SRFI-10 - Hash-Comma Reader Extension

The module (srfi srfi-10) implements the syntax extension #,(), also called hash-comma, which is defined in SRFI-10.

The support for SRFI-10 consists of the procedure define-reader-ctor for defining new reader constructors and the read syntax form

     #,(ctor datum ...)

where ctor must be a symbol for which a read constructor was defined previously, using define-reader-ctor.

Example:

     (define-reader-ctor 'file open-input-file)
     (define f '#,(file "/etc/passwd"))
     (read-line f)
     ⇒ "root:x:0:0:root:/root:/bin/bash"

Please note the quote before the #,(file ...) expression. This is necessary because ports are not self-evaluating in Guile.