Read an s-expression from the input port port, or from the current input port if port is not specified. Any whitespace before the next token is discarded.
The behaviour of Guile's Scheme reader can be modified by manipulating its read options.
Display the current settings of the read options. If setting is omitted, only a short form of the current read options is printed. Otherwise if setting is the symbol
help, a complete options description is displayed.
The set of available options, and their default values, may be had by
invoking read-options at the prompt.
scheme@(guile-user)> (read-options)
(square-brackets keywords #f positions)
scheme@(guile-user)> (read-options 'help)
copy no Copy source code expressions.
positions yes Record positions of source code expressions.
case-insensitive no Convert symbols to lower case.
keywords #f Style of keyword recognition: #f, 'prefix or 'postfix.
r6rs-hex-escapes no Use R6RS variable-length character and string hex escapes.
square-brackets yes Treat `[' and `]' as parentheses, for R6RS compatibility.
The boolean options may be toggled with read-enable and
read-disable. The non-boolean keywords option must be set
using read-set!.
Modify the read options.
read-enableshould be used with boolean options and switches them on,read-disableswitches them off.read-set!can be used to set an option to a specific value.
For example, to make read fold all symbols to their lower case
(perhaps for compatibility with older Scheme code), you can enter:
(read-enable 'case-insensitive)
For more information on the effect of the r6rs-hex-escapes option, see
(see String Syntax).