[Larceny-users] Bug - get-string-n

[Ray Racine]

There is a fence post bug in get-string-n in portio.sch. The do loop
reads a char on loop initialization and then one for count iterations.
Therefore one more then count chars are consumed in the call to
get-string-n.

See sample below. Notice '5' was skipped.


Ray

----

Process scheme finished
Larceny v0.961 "Fluoridation" (Feb 4 2008 23:49:20,
precise:Linux:unified)
larceny.heap, built on Mon Feb 4 23:53:29 EST 2008
ERR5RS mode (no libraries have been imported)

(import (rnrs))

Autoloading (rnrs)
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Autoloading (rnrs io ports)
Autoloading (larceny deprecated)
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Autoloading (rnrs exceptions)
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Autoloading (rnrs records procedural)
Autoloading (rnrs control)
Autoloading (rnrs sorting)
Autoloading (rnrs bytevectors)
Autoloading (rnrs unicode)

(import (rnrs io ports))
(define ip (open-string-input-port "12345678"))
(get-string-n ip 4)

"1234"

(get-string-n ip 4)

"678"


Notice '5' was skipped.

[William D Clinger]

There is a fence post bug in get-string-n in portio.sch....

Thanks for reporting this, Ray. This has been logged as
ticket #523. Two other bugs you had reported previously
have been logged as tickets #524 and #525.

Will