Hi!

I have the error message:
source/url.cache.d(20,16): Error: function url.Cache.UrlCache.doRequest has no return statement, but is expected to return a value of type string

Inserting dummy return statement doesn't help. final switch / switch with default - no matter.

As I understand compiler must detect when end of function is unreachable (and in fact it detects it - see comment about return ""; line) and do not try to check for return value. Is this my or compiler's error here?

>dmd --version
DMD64 D Compiler v2.069.0
Copyright (c) 1999-2015 by Digital Mars written by Walter Bright


[code]
module url.Cache;

import std.conv;
import core.exception;
import mysql.d;
import std.digest.md;
import std.net.curl;

enum Method { GET="GET", POST="POST" }

class UrlCache
{
// ...
	public string doRealRequest(string url, Method method)
	{
		final switch(method)
		{
			case Method.GET:
				return std.net.curl.get!AutoProtocol(url).text;
			case Method.POST:
				return std.net.curl.post(url, []).text;
		}
		// return ""; // produces 'statement is not reachable' warning, don't fix the problem
	}
// ...	
}
[/code]

On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
> Inserting dummy return statement doesn't help. final switch / switch with default - no matter.


Try inserting assert(0); instead of a dummy return.

On Saturday, 7 November 2015 at 00:27:02 UTC, Adam D. Ruppe wrote:
> On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
>> Inserting dummy return statement doesn't help. final switch / switch with default - no matter.
>
>
> Try inserting assert(0); instead of a dummy return.

 Done, no difference.

On Saturday, 7 November 2015 at 00:30:29 UTC, crimaniak wrote:
> On Saturday, 7 November 2015 at 00:27:02 UTC, Adam D. Ruppe wrote:
>> On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
>>> Inserting dummy return statement doesn't help. final switch / switch with default - no matter.
>>
>>
>> Try inserting assert(0); instead of a dummy return.
>
>  Done, no difference.

Wow, that impossible. You switch is well final.

here DMD 2.068, linux x86_64 the folling compiles and runs:

----
enum Method { GET="GET", POST="POST" }

class UrlCache
{
	public string doRealRequest(string url, Method method)
	{
		final switch(method)
		{
			case Method.GET:
				return std.net.curl.get!AutoProtocol(url).idup;
			case Method.POST:
				return std.net.curl.post(url, []).idup;
		}
    }
}

void main()
{auto test = new UrlCache;}
----

are you sure that the error you get doesnt come from another location ?!

On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
> Hi!
>
> I have the error message:
> source/url.cache.d(20,16): Error: function url.Cache.UrlCache.doRequest has no return statement, but is expected to return a value of type string
>
> [...]

Because the "switch" is marked as "final", eventually one of cases will be followed. Because both cases have a "return" point, code will never get out of switch statement. So the compiler acts correctly.

On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
> [...]
> url.Cache.UrlCache.doRequest has no return statement, but is expected to return a value of type string
> [...]
> 	public string doRealRequest(string url, Method method)


You posted the wrong code sample: your code shows doRealRequest but the message is about doRequest !

On Saturday, 7 November 2015 at 06:02:49 UTC, BBaz wrote:
> On Saturday, 7 November 2015 at 00:21:57 UTC, crimaniak wrote:
>> [...]
>> url.Cache.UrlCache.doRequest has no return statement, but is expected to return a value of type string
>> [...]
>> 	public string doRealRequest(string url, Method method)
>
>
> You posted the wrong code sample: your code shows doRealRequest but the message is about doRequest !

 Yes! It's just my inattention. Thanks!

p.s. Don't program at 3 am