ref: 218e5bd8256e190fb0b71f4178dc107a7b7bfc74
parent: 469769a5581ce0909cc3bec7fc59d8e71b9fe58b
author: Ori Bernstein <[email protected]>
date: Wed Dec 25 17:58:39 EST 2013
Make peeking handle EOF correctly.
--- a/bio.myr
+++ b/bio.myr
@@ -45,8 +45,8 @@
generic getle : (f : file# -> std.option(@a::(tctest,tcnum,tcint)))
/* peeking */
- const peekb : (f : file# -> byte)
- const peekc : (f : file# -> char)
+ const peekb : (f : file# -> std.option(byte))
+ const peekc : (f : file# -> std.option(char))
/* delimited read; returns freshly allocated buffer. */
const readln : (f : file# -> std.option(byte[:]))
@@ -250,7 +250,10 @@
var b
var len
- b = peekb(f)
+ if !ensureread(f, 1)
+ -> false
+ ;;
+ b = f.rbuf[f.rstart]
if b & 0x80 == 0 /* 0b0xxx_xxxx */
len = 1
elif b & 0xe0 == 0xc0 /* 0b110x_xxxx */
@@ -333,16 +336,20 @@
/* peeks a single byte from an input stream */
const peekb = {f- ensureread(f, 1)
- -> f.rbuf[f.rstart]
+ if !ensureread(f, 1)
+ -> `std.None
+ else
+ -> `std.Some f.rbuf[f.rstart]
+ ;;
}
/* peeks a single character from a utf8 encoded input stream */
const peekc = {fif !ensurecodepoint(f)
- -> -1
+ -> `std.None
+ else
+ -> `std.Some std.decode(f.rbuf[f.rstart:f.rend])
;;
- -> std.decode(f.rbuf[f.rstart:f.rend])
}
/*
--- a/test/bio-peek.myr
+++ b/test/bio-peek.myr
@@ -11,17 +11,35 @@
| `std.None: std.fatal(1, "Unable to open data file")
;;
- std.assert(bio.peekb(f) == 0x30, "wrong byte value read from datafile")
- std.assert(bio.peekc(f) == '0', "wrong char value read from datafile")
+ std.assert(peekb(f) == 0x30, "wrong byte value read from datafile")
+ std.assert(peekc(f) == '0', "wrong char value read from datafile")
bio.read(f, buf[:4]) /* skip ahead 4 bytes */
- std.assert(bio.peekb(f) == 0x34, "wrong byte value read from datafile")
- std.assert(bio.peekc(f) == '4', "wrong char value read from datafile")
+ std.assert(peekb(f) == 0x34, "wrong byte value read from datafile")
+ std.assert(peekc(f) == '4', "wrong char value read from datafile")
bio.read(f, buf[:]) /* skip ahead 64k */
- std.assert(bio.peekb(f) == 0x30, "wrong byte value read from datafile")
- std.assert(bio.peekc(f) == '0', "wrong char value read from datafile")
+ std.assert(peekb(f) == 0x30, "wrong byte value read from datafile")
+ std.assert(peekc(f) == '0', "wrong char value read from datafile")
bio.close(f);
std.put("Succeded peeeking values\n")+}
+
+const peekc = {f+ match bio.peekc(f)
+ | `std.Some c: -> c
+ | `std.None:
+ std.put("eof")+ -> -1
+ ;;
+}
+
+const peekb = {f+ match bio.peekb(f)
+ | `std.Some b: -> b
+ | `std.None:
+ std.put("eof")+ -> -1
+ ;;
}