Please help me understand this function signature: std.stdio.File.byLine

[Scotpip]

Hi folks

Settling down to write my first app but have come to a grinding 
halt. This is my first system-level language so I'm afraid I'll 
be asking some naïve questions.

All I'm trying to do is read a text file with Windows line 
endings into an array for line-by-line processing.

The relevant function appears to be 
[std.stdio.File.byLine](https://dlang.org/library/std/stdio/file.by_line.html).

The default isn't breaking the lines properly, so I have to pass 
in the line ending. But the signature has me baffled:

```
auto byLine(Terminator, Char) (
   KeepTerminator keepTerminator = No.keepTerminator,
   Terminator terminator = '\x0a'
)
if (isScalarType!Terminator);

auto byLine(Terminator, Char) (
   KeepTerminator keepTerminator,
   Terminator terminator
)
if (is(immutable(ElementEncodingType!Terminator) == 
immutable(Char)));
```

To specify the line ending, it appears to be asking for a type 
"Terminator" which I can't find in the library. Doing the obvious 
doesn't work:

```
// Err: cannot deduce function from argument types
myFile.byLine(`\r\n`);
```
Also, how would you specify the Char type as a parameter?


The examples are unenlightening as they only show the default 
case, so any help would be much appreciated. Any wider tips on 
how to read these cryptic signatures would be a bonus!