The Annoyance Filter.pdf - Fourmilab

§131 ANNOYANCE-FILTER MAIL FOLDER 115
131. The nextByte method is used by the tokenParser when scouring byte stream data for plausible
strings. It must only be used when byteStream is set. It returns the next byte from the stream or −1
at the end of the stream and cancels byteStream mode. How we get out of here depends on a fairly
intimate mutual understanding between mailFolder and tokenParser of each other’s innards.
〈 Class implementations 11 〉 +≡
int mailFolder ::nextByte (void)
{
assert(mdp ≠ Λ);
int c = mdp ⃗ getDecodedChar ( );
if (c < 0) {
byteStream = false ;
if (Annotate (’d’)) {
ostringstream os ;
os ≪ "End␣of␣byte␣stream.␣␣Deactivating␣byte␣stream␣parser.";
reportParserDiagnostic(os );
}
}
return c;
}