24 lines
1.2 KiB
Plaintext
24 lines
1.2 KiB
Plaintext
The SRFI-10 structure defines an octothorpe reader syntax, comma, as specified
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in SRFI 10. It also defines a procedure, DEFINE-READER-CONSTRUCTOR, for user-
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defined reader constructors.
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(DEFINE-READER-CONSTRUCTOR <symbol> <procedure>) -> unspecific ;procedure
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Define SYMBOL to be a reader constructor, calling PROCEDURE at read-time;
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that is, for any instances of #,(SYMBOL <arg> ...), PROCEDURE will be applied
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to the arguments ARG ....
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The test/ directory contains a couple of examples. A structure whose name is
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of the form SRFI-10-TEST/<foo> corresponds to test/<foo>.scm.
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This implementation of SRFI 10 is not perfect: it will give errors regarding
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invalid data in quotations if your reader constructors construct anything that
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isn't an S-expression, and all that's only if you quote those; if you don't
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quote the things, you'll get even worse errors.
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There is one built-in reader constructor:
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#,(DEFINE-READER-CONSTRUCTOR <name> <procedure-expression>) ;reader constructor
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Just like the DEFINE-READER-CONSTRUCTOR procedure, except that NAME must be a
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literal symbol, and this operates at read-time. PROCEDURE-EXPRESSION will be
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evaluated in the what interaction environment is in state during read-time.
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