method has no return statement with switch
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]
Re: method has no return statement with switch
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.
Re: method has no return statement with switch
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.
Re: method has no return statement with switch
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 ?!
Re: method has no return statement with switch
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.
Re: method has no return statement with switch
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 !
Re: method has no return statement with switch
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
