bit syntax documentation

Bjorn Gustavsson <>
Tue Apr 3 17:26:35 CEST 2001


Thanks for pointing out the error.

The head should have been

  foo(<<X:7/binary-unit:1,Y:1/binary-unit:1>>) ->

We will correct the documentation in the R8 release.

/Bjorn

Ulf Wiger <> writes:

> In the documentation for the bit syntax, I read the following:
> 
> 
> "A segment of type binary must have a size evenly divisible by 8. 
> 
>      This means that the following head will never match: 
> 
>      foo(<<X:7/binary,Y:1/binary>>) ->"
> 
> (http://www.erlang.org/doc/r7b/doc/extensions/bit_syntax.html#6.6)
> 
> Since my code didn't work as expected, I tried to verify this:
> 
> 
> 
> 30> F = fun(<<X:7/binary,Y:1/binary>>) -> {X,Y}; (Other) -> Other
> end.
> #Fun<erl_eval.17.63972567>
> 31> F(<<"12345678">>).                                                     
> {<<49,50,51,52,53,54,55>>,<<56>>}
> 
> 
> 
> In other words, the head described in the manual matches just fine.
> 
> Comments?
> 
> /Uffe
> -- 
> Ulf Wiger                                    tfn: +46  8 719 81 95
> Senior System Architect                      mob: +46 70 519 81 95
> Strategic Product & System Management    ATM Multiservice Networks
> Data Backbone & Optical Services Division      Ericsson Telecom AB
> 

-- 
Björn Gustavsson            Ericsson Utvecklings AB
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