I’m not sure what you are saying… If you have Gb/s, then you need to divide by 8 to get GO/s as well…
Though I admit, abbreviations were a little bit more clear… Especially as not everyone follows the convention to lowercase the b when bits are meant…
I prefer just spelling those things out…
And confusion about Mibi vs Mega is much much worse than bytes vs bits…
I agree.
I was not there when binaries were introduced into Erlang, but what I heard is that they were first used to store compiled Erlang code (for JAM at that time). That was necessary in order to implement erl_boot_server that allows a diskless client to fetch code to be loaded from another node.
The idea to use binaries to store text strings is of much later date. Originally, all binaries were reference-counted, which is practical for storing a relatively small number of large binaries, but not for storing many small binaries. OTP R7 introduced the bit syntax and heap binaries. (See How binaries are implemented for more information.)
Snap! Good catch! Is there any way to do pattern matching within <<>> to grab the first character (even a multi-byte character)?
Something where
iex> <<x::something????, rest::binary>> = "über"
"über"
iex> x
ü
I don’t think so, because you can’t know how many bytes or codepoints a “character” consists of.
utf8 will extract the codepoint, which you can then reassemble:
iex(1)> <<c::utf8, _::binary>> = "über"
"über"
iex(2)> c
252
iex(3)> <<c::utf8>>
"ü"
Yep but even then it often doesn’t match a user perceived character, i.e. a grapheme cluster.
I noticed there was some confusion about codepoints vs graphemes in this thread so thought I’d plug the Unicode section of Adopting Erlang :), Hard Things to Get Right | Adopting Erlang
I wonder if you could write a guard clause like:
def my_func(x <> rest)) when x in ["ü", "ß", "†"], do: # ....
?
No, as a <> b is sugar for <<a::binary, b::binary>> and you cannot match binaries of unknown size.
What you can do is this:
def f(<<x::utf8, _::binary>>) when x in ~c[üéæ], do: ...
# or
def f(<<x::utf8, _::binary>>) when <<x::utf8>> in ~w[ü é æ], do: ...
This does of course only work if the combined normalisation is used and not if the grapheme is combined from two codepoints.