Radio Shack TRS-80 Trsdos & Disk Basic Reference Manual page 141

DISK BASIC
Then
the statement:
PRINT CVD<GR0S5PflY$>-TRXES
prints the result
of
the difference,
13123.38-TAXES.
Whereas
the
statement:
PRINT GROSSPRY$-TflXES
will
produce
a
TYPE MISMATCH
error,
since string values
cannot be
used
in
arithmetic expressions.
Using the
same example,
the statement
fl#=CVD<QROSSPflV*)
assigns
the
numeric
value 13 123.38
to
the double-precision
variable
A#.
EOF
(end-of-file
detector)
EOF(nmexp)
where
nmexp
specifies a
file
buffer,
nmexp=\,2,
... ,15
This function checks to see
whether
all
characters
up
to
the end-of-
file
marker have been
accessed, so
you
can avoid
INPUT PAST
END
errors
during sequential input.
Assuming
nmexp
specifies
an
open
file,
then
EOF(nmexp)
returns
(false)
when
the
EOF
record has not yet
been
read,
and -1
(true)
when
it
has
been
read.
Examples:
IF
EGR5)
THEN PR
I
NT "END OF
FILE"FILENM$
IF EQFCNir/.)
THEN CLOSE
NIT/.
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