In https://github.com/D-Programming-Language/phobos/pull/3534

I'm in need of a generic and correct definition of

    template isSortedRange(T, alias pred = "a < b")

at

https://github.com/D-Programming-Language/phobos/pull/3534/files#diff-9f63c74383984a09f5bf578493892e27R1005

To make it general we want it to support `pred` argument of types other than `string`, typically

    binaryFun!"a < b"

Specifically, we want `isSortedRange` to "understand" that

    binaryFun!"a < b"
    binaryFun!"a<b"

are equvialent and

    binaryFun!"a < b"
    binaryFun!"a > b"

are not (opposites). I'm guessing there is compile-time-parsing somewhere in Phobos that already does this. Could/Should this be extracted and reused?

Destroy!

On Monday, 17 August 2015 at 09:23:56 UTC, Per Nordlöw wrote:
> To make it general we want it to support `pred` argument of types other than `string`, typically

If binaryFun!"..." are used as template alias parameters in all cases is it currently possible to compare these lambdas for equality?

On 08/17/2015 12:13 PM, "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow@gmail.com>" wrote:
> On Monday, 17 August 2015 at 09:23:56 UTC, Per Nordlöw wrote:
>> To make it general we want it to support `pred` argument of types
>> other than `string`, typically
>
> If binaryFun!"..." are used as template alias parameters in all cases is
> it currently possible to compare these lambdas for equality?

import std.functional: binaryFun;

alias x=binaryFun!"a+b";
alias y=binaryFun!"a+b";
alias z=binaryFun!"a-b";
static assert(__traits(isSame,x,y));
static assert(!__traits(isSame,y,z));

enum binaryFunString(alias x:binaryFun!T,T...)=T[0];

static assert(binaryFunString!x=="a+b");
static assert(binaryFunString!y=="a+b");
static assert(binaryFunString!z=="a-b");

On 08/17/2015 02:33 PM, Timon Gehr wrote:
> enum binaryFunString(alias x:binaryFun!T,T...)=T[0];
>
> static assert(binaryFunString!x=="a+b");
> static assert(binaryFunString!y=="a+b");
> static assert(binaryFunString!z=="a-b");

Note that the remaining template arguments to binaryFun are important as well, they give the parameter names.

You might want to use std.traits.TemplateArgsOf.

On Monday, 17 August 2015 at 12:33:28 UTC, Timon Gehr wrote:
> import std.functional: binaryFun;
>
> alias x=binaryFun!"a+b";
> alias y=binaryFun!"a+b";
> static assert(__traits(isSame,x,y));

Not quite what we want, because

    alias x=binaryFun!"a+b";
    alias y=binaryFun!"a + b";
    static assert(__traits(isSame,x,y));

fails for me.

Can we be dumb for now and just remove space in string?