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digitalmars.D.learn - Bug in documentation or misunderstanding it?

reply Suliman <evermind live.ru> writes:
I read docs and can't understand what's wrong. Or I am do not 
understand it, or there is come mistake.

Let's look at function 
https://dlang.org/phobos/std_stdio.html#.File.byLine

auto byLine(Terminator = char, Char = char)(KeepTerminator 
keepTerminator = No.keepTerminator, Terminator terminator = 
'\x0a')

what does mean first groups of scope: (Terminator = char, Char = 
char) ?

The second one as I understand it's options symbol `=` mean that 
there is some default values, so if I will call function I can do 
not set them, so predefined values will be used.

Am I right? And If I do not want predefined I can pass my own 
like:
`byLine(No.keepTerminator, 'SomeLetter')`

for example: `file.byLine(No.keepTerminator, 'a')`

But when I compile simple example I am getting compilation error: 
`undefined identifier 'No'`

Where I am wrong?
Jan 26 2017
next sibling parent Stefan Koch <uplink.coder googlemail.com> writes:
On Thursday, 26 January 2017 at 17:38:59 UTC, Suliman wrote:

 I read docs and can't understand what's wrong. Or I am do not 
 understand it, or there is come mistake.

 [...]


You have to import typecons.
Jan 26 2017
prev sibling parent reply "H. S. Teoh via Digitalmars-d-learn" <digitalmars-d-learn puremagic.com> writes:
On Thu, Jan 26, 2017 at 05:38:59PM +0000, Suliman via Digitalmars-d-learn wrote:

 I read docs and can't understand what's wrong. Or I am do not understand it,
 or there is come mistake.
 
 Let's look at function https://dlang.org/phobos/std_stdio.html#.File.byLine
 
 auto byLine(Terminator = char, Char = char)(KeepTerminator keepTerminator =
 No.keepTerminator, Terminator terminator = '\x0a')
 
 what does mean first groups of scope: (Terminator = char, Char = char) ?


Those are compile-time parameters. You specify them in a compile-time
argument list using the !(...) construct, for example:

	auto lines = File("myfile.txt")
		.byLine!(dchar, char)(Yes.keepTerminator, '\u263a');


T

-- 
If lightning were to ever strike an orchestra, it'd always hit the conductor
first.
Jan 26 2017
parent reply Suliman <evermind live.ru> writes:
On Thursday, 26 January 2017 at 17:52:24 UTC, H. S. Teoh wrote:

 On Thu, Jan 26, 2017 at 05:38:59PM +0000, Suliman via 
 Digitalmars-d-learn wrote:

 I read docs and can't understand what's wrong. Or I am do not 
 understand it, or there is come mistake.
 
 Let's look at function 
 https://dlang.org/phobos/std_stdio.html#.File.byLine
 
 auto byLine(Terminator = char, Char = char)(KeepTerminator 
 keepTerminator =
 No.keepTerminator, Terminator terminator = '\x0a')
 
 what does mean first groups of scope: (Terminator = char, Char 
 = char) ?


 Those are compile-time parameters. You specify them in a 
 compile-time argument list using the !(...) construct, for 
 example:

 	auto lines = File("myfile.txt")
 		.byLine!(dchar, char)(Yes.keepTerminator, '\u263a');


 T


So I am right about others items about for example that `=` is 
optional?
Jan 26 2017
parent reply Suliman <evermind live.ru> writes:
On Thursday, 26 January 2017 at 18:42:29 UTC, Suliman wrote:

 On Thursday, 26 January 2017 at 17:52:24 UTC, H. S. Teoh wrote:

 On Thu, Jan 26, 2017 at 05:38:59PM +0000, Suliman via 
 Digitalmars-d-learn wrote:

 I read docs and can't understand what's wrong. Or I am do not 
 understand it, or there is come mistake.
 
 Let's look at function 
 https://dlang.org/phobos/std_stdio.html#.File.byLine
 
 auto byLine(Terminator = char, Char = char)(KeepTerminator 
 keepTerminator =
 No.keepTerminator, Terminator terminator = '\x0a')
 
 what does mean first groups of scope: (Terminator = char, 
 Char = char) ?


 Those are compile-time parameters. You specify them in a 
 compile-time argument list using the !(...) construct, for 
 example:

 	auto lines = File("myfile.txt")
 		.byLine!(dchar, char)(Yes.keepTerminator, '\u263a');


 T


 So I am right about others items about for example that `=` is 
 optional?


Why this code is work: `file.byLine(KeepTerminator.no, 'm')`
Jan 26 2017
parent "H. S. Teoh via Digitalmars-d-learn" <digitalmars-d-learn puremagic.com> writes:
On Thu, Jan 26, 2017 at 06:47:21PM +0000, Suliman via Digitalmars-d-learn wrote:

 On Thursday, 26 January 2017 at 18:42:29 UTC, Suliman wrote:

 On Thursday, 26 January 2017 at 17:52:24 UTC, H. S. Teoh wrote:

 On Thu, Jan 26, 2017 at 05:38:59PM +0000, Suliman via
 Digitalmars-d-learn wrote:

 I read docs and can't understand what's wrong. Or I am do not
 understand it, or there is come mistake.
 
 Let's look at function
 https://dlang.org/phobos/std_stdio.html#.File.byLine
 
 auto byLine(Terminator = char, Char = char)(KeepTerminator
 keepTerminator = No.keepTerminator, Terminator terminator =
 '\x0a')
 
 what does mean first groups of scope: (Terminator = char, Char =
 char) ?


 
 Those are compile-time parameters. You specify them in a
 compile-time argument list using the !(...) construct, for
 example:
 
 	auto lines = File("myfile.txt")
 		.byLine!(dchar, char)(Yes.keepTerminator, '\u263a');
 
 
 T


 
 So I am right about others items about for example that `=` is optional?


 
 Why this code is work: `file.byLine(KeepTerminator.no, 'm')`


Yes, the `=` means the parameter has a default value. This applies to
both compile-time parameters and runtime parameters. So:

	file.byLine(KeepTerminator.no);

is the same as:

	file.byLine!(char, char)(No.keepTerminator, '\x0a');


T

-- 
There are 10 kinds of people in the world: those who can count in binary, and
those who can't.
Jan 27 2017