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SUBROUTINE PRSEHR (BUFFER,BEGBUF,ENDBUF,MAXBUF)
C$ (Parse Internal - Edit, Help, and Recognition Characters)
C$ Given a text buffer, BUFFER(*), containing ASCII ordinals,
C$ process entries BUFFER(BEGBUF) .. BUFFER(ENDBUF),
C$ converting edit, help, and recognition sequences to
C$ internal codes and implementing their actions.
C$
C$ Letter-case in an editing character pair is not
C$ significant, but is preserved. Editing characters are
C$ deleted from the buffer. Note that a quoted editing
C$ character has no editing function and is preserved. A 0
C$ repeat count is equivalent to a repeat count of 1, and a
C$ repeat count followed by a quoted character applies to the
C$ quoted character, not to the quote sequence.
C$
C$ The substitutions are carried out by replacing the first
C$ character of an edit character pair by the deleted
C$ character flag, DELCHR, so BEGBUF is unchanged on return.
C$ The second character of a pair is replaced by EDPAIR.
C$ ENDBUF will be increased up to the limit of MAXBUF in
C$ response to any repeat counts. If ENDBUF = MAXBUF on
C$ return, trailing characters have been dropped from the
C$ buffer. It is assumed that BUFFER(MAXBUF+1) is addressable
C$ and contains a special marker that is not in the ASCII
C$ range 0..127. On return, ENDBUF is reduced if necessary to
C$ guarantee that BUFFER(ENDBUF) does not contain DELCHR,
C$ thereby freeing buffer space.
C$ (19-NOV-82)