2 Integers

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integer->bytes

bytes->integer

integer-bytes-length

integer-bytes-length<=?

write-integer

read-integer

8.18

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2Integers🔗 i

(require binaryio/integer ) package: binaryio-lib

procedure
( integer->bytes val
size
signed?
[ big-endian?
dest
start]) → bytes?
val:exact-integer?
size:exact-positive-integer?
signed?:boolean?
big-endian?:boolean? =#t
dest:(and/c bytes? (not/c mutable?))=(make-bytes size)
start:exact-nonnegative-integer? =0

Like integer->integer-bytes , except that arbitrary size arguments are supported, and big-endian? defaults to #t (network byte order) rather than the host byte order.

Examples:

> (integer->bytes -13#t)

#"377円377円377円"
> (integer->bytes (expt 2331)18#f)

#"22円305円U2375円302円332円26円_5円6円235円q30円~253円6円247円"

procedure
( bytes->integer bstr
signed?
[ big-endian?
start
end]) → exact-integer?
bstr:bytes?
signed?:boolean?
big-endian?:boolean? =#t
start:exact-nonnegative-integer? =0
end:exact-nonnegative-integer? =(bytes-length bstr)

Like integer-bytes->integer , except that arbitrary sizes—that is, (- endstart)—are supported, and big-endian? defaults to #t (network byte order) rather than the host byte order.

procedure
( integer-bytes-length valsigned?)→exact-nonnegative-integer?
val:exact-integer?
signed?:boolean?

Returns the number of bytes needed to encode val, including the sign bit if signed? is true.

Examples:

> (integer-bytes-length 127#t)

1
> (integer-bytes-length 128#t)

2

procedure
( integer-bytes-length<=? valnbytessigned?)→boolean?
val:exact-integer?
nbytes:exact-nonnegative-integer?
signed?:boolean?

Equivalent to (<= (integer-bytes-length valsigned?)nbytes), but can be faster for small values of nbytes.

procedure
( write-integer val
size
signed?
[ out
big-endian?]) → void?
val:exact-integer?
size:exact-positive-integer?
signed?:boolean?
out:output-port? =(current-output-port )
big-endian?:boolean? =#t

Writes the encoding of val to out.

Equivalent to (write-bytes (integer->bytes valsizesigned?big-endian?)out).

procedure
( read-integer sizesigned?[inbig-endian?])→exact-integer?
size:exact-positive-integer?
signed?:boolean?
in:input-port? =(current-input-port )
big-endian?:boolean? =#t

Reads size bytes from in and decodes it as an integer. If fewer than size bytes are available before the end of input, an error is raised.

Equivalent to (bytes->integer (read-bytes* sizein)signed?big-endian?).

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