From e69407b2e9efb230814fbf356975c22f5a826767 Mon Sep 17 00:00:00 2001 From: Peter Saxton Date: Thu, 28 May 2020 14:15:02 +0100 Subject: add a binary module --- src/gleam/binary.gleam | 23 +++++++++++++++++++++++ src/gleam/binary_native.erl | 12 ++++++++++++ 2 files changed, 35 insertions(+) create mode 100644 src/gleam/binary.gleam create mode 100644 src/gleam/binary_native.erl (limited to 'src') diff --git a/src/gleam/binary.gleam b/src/gleam/binary.gleam new file mode 100644 index 0000000..1fa54a8 --- /dev/null +++ b/src/gleam/binary.gleam @@ -0,0 +1,23 @@ +//// Working with raw binary data. +//// The Binary type should be used instead of a String type when not utf8 encoded. + +pub external type Binary + +/// Convert a utf8 String type into a raw Binary type. +pub external fn from_string(String) -> Binary = + "gleam_stdlib" "identity" + +/// Extracts the part of a binary. +/// +/// Binary part will start at given position and continue up to specified length. +/// A negative length can be used to extract bytes at the end of a binary: +pub external fn part(string: Binary, position: Int, length: Int) -> Binary = "binary" "part" + + +/// Returns an integer which is the number of bytes in the binary. +pub external fn byte_size(Binary) -> Int = + "erlang" "byte_size" + +// Not sure these will be necessary with bit syntax for for now I think they are +pub external fn int_to_u32(Int) -> Result(Binary, Nil) = "binary_native" "int_to_u32" +pub external fn int_from_u32(Binary) -> Result(Int, Nil) = "binary_native" "int_from_u32" diff --git a/src/gleam/binary_native.erl b/src/gleam/binary_native.erl new file mode 100644 index 0000000..d7e774c --- /dev/null +++ b/src/gleam/binary_native.erl @@ -0,0 +1,12 @@ +-module (binary_native). +-export ([int_to_u32/1, int_from_u32/1]). + +int_to_u32(I) when 0 =< I, I < 4294967296 -> + {ok, <>}; +int_to_u32(_) -> + {error, nil}. + +int_from_u32(<>) -> + {ok, I}; +int_from_u32(_) -> + {error, nil}. -- cgit v1.2.3