This is really a extension of what we talked about in StringCheckForChar. SRFI-13 provides string-filter and string-delete functions, which are inverse operations:
500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)
The first thing to note is that the SRFI-13 implementation that ships with PLT, as well as the one provided by Schematics, differ from the spec in that they swap the order of the 1st two arguments. This can be a little confusing.
Second, both functions allow you to specify the filter argument in 3 ways: as a character, a char-set, or a predicate. For example, the following 3 are equivalent methods of stripping a hyphen from a string:
500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)
It's useful to be able to define a function make-filter which returns a function with arguments partially bound.
500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)
Once you've defined this, you can call the result directly, or give it a better name:
500 Can't connect to 127.0.0.1:8778 (connect: Connection refused)
-- GordonWeakliem - 19 Apr 2004
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