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digitalmars.D.learn - What is Base64 part in Base64.encode

reply zabruk70 <sorry noem.ail> writes:
I look to std.base64 module source.
And dont unerstand what is the "Base64" part in 
"Base64.encode(data)" example.
I see std.base64 module use template Base64Impl.
I see alias Base64 = Base64Impl!...
But down understand.
Base64 not module, not structure, not class?
Template Base64Impl shoud produce function?

I want create base32 encoder/decoder for example.
But i dont need template.
So how i can write Base32.encode()?
By creating class Base32 with encode() member.
By creating structute Base32 with encode() member.
Any other options?

Thanx.
May 14
parent reply Moritz Maxeiner <moritz ucworks.org> writes:
On Sunday, 14 May 2017 at 20:04:07 UTC, zabruk70 wrote:
 I look to std.base64 module source.
 And dont unerstand what is the "Base64" part in 
 "Base64.encode(data)" example.
 I see std.base64 module use template Base64Impl.
 I see alias Base64 = Base64Impl!...
 But down understand.
 Base64 not module, not structure, not class?
The full line is `alias Base64 = Base64Impl!('+', '/');`, which reads as (refer to [1][2]): The symbol Base64 refers to the Base64Impl template instantiated with the template parameters '+' and '/'.
 Template Base64Impl shoud produce function?
I don't understand what you're trying to express here. As Base64Impl's documentation states[3], it contains a generic Base64 implementation for which you can customize some of the encoding characters at compile time via template parameters.
 I want create base32 encoder/decoder for example.
 But i dont need template.
 So how i can write Base32.encode()?
 By creating class Base32 with encode() member.
 By creating structute Base32 with encode() member.
 Any other options?
You can create a base32 encoder however you like, D has lots of different ways you could approach this; you can even do it in a C way with two functions base32_encode / base32_decode. Just pick whatever you like. PS: Please spellcheck. [1] https://dlang.org/spec/declaration.html#alias [2] https://dlang.org/spec/template.html [3] https://github.com/dlang/phobos/blob/master/std/base64.d#L108
May 14
parent reply zabruk70 <sorry noem.ail> writes:
On Sunday, 14 May 2017 at 21:22:20 UTC, Moritz Maxeiner wrote:
 The full line is `alias Base64 = Base64Impl!('+', '/');`
Yes. When we use it like this: const(char)[] encoded = Base64.encode(data); then template instantiated and produce ... what?
 I don't understand what you're trying to express here.
What kind of symbols (class name, structure name, type) can be used with dot in D language? What produced by template instantiation `Base64Impl!('+', '/')` then i use alias `Base64`?
 You can create a base32 encoder however you like, D has lots of 
 different ways you could approach this; you can even do it in a
But i want mimic std.base64 syntax. I want to write something like string encoded = Base32.encode(data); And i don't want to use template.
May 14
parent Moritz Maxeiner <moritz ucworks.org> writes:
On Sunday, 14 May 2017 at 21:34:35 UTC, zabruk70 wrote:
 On Sunday, 14 May 2017 at 21:22:20 UTC, Moritz Maxeiner wrote:
 The full line is `alias Base64 = Base64Impl!('+', '/');`
Yes. When we use it like this: const(char)[] encoded = Base64.encode(data); then template instantiated and produce ... what?
Have you read the language specification I linked to? Base64 refers to a (fully) parametrized template. If you use the symbol Base64, you will access its instantiation; '.encode' then accesses the member "encode" in the scope of that template instance, which happens to be a function. That function then gets called with "data" as its argument and returns the encoded data.
 I don't understand what you're trying to express here.
What kind of symbols (class name, structure name, type) can be used with dot in D language?
Pretty much any symbol. Any type (or alias to one) will at least have properties[1] and any variable will be open to UFCS[2].
 What produced by template instantiation `Base64Impl!('+', '/')`
 then i use alias `Base64`?
I'm sorry, but I have no idea what you're trying to convey here.
 You can create a base32 encoder however you like, D has lots 
 of different ways you could approach this; you can even do it 
 in a
But i want mimic std.base64 syntax. I want to write something like string encoded = Base32.encode(data); And i don't want to use template.
Then use a struct with static member functions: struct Base32 { static [...] encode([...]) { [...] } static [...] decode([...]) { [...] } } [1] https://dlang.org/spec/property.html [2] https://tour.dlang.org/tour/en/gems/uniform-function-call-syntax-ufcs
May 14