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digitalmars.D.learn - fromStringz for wide characters

reply John Burton <john.burton jbmail.com> writes:
std.string.fromStringz will create me a string from a null 
terminated array of characters. But I have a zero terminated 
array of "short"s (from a win32 api call) which I'd like to turn 
into a wstring. But there doesn't seem to be a function to do 
this.

Do I need to write my own, or am I missing something?
Sep 05
parent reply Jonathan M Davis via Digitalmars-d-learn writes:
On Tuesday, September 05, 2017 08:15:04 John Burton via Digitalmars-d-learn 
wrote:
 std.string.fromStringz will create me a string from a null
 terminated array of characters. But I have a zero terminated
 array of "short"s (from a win32 api call) which I'd like to turn
 into a wstring. But there doesn't seem to be a function to do
 this.

 Do I need to write my own, or am I missing something?
I'm fairly certain that to!wstring will do it, but it will definitely allocate, whereas fromStringz just slices what it's given. I don't think that there's currently a wchar equivalent to fromStringz, but it would be pretty trivial to write if you didn't want to use to!wstring. fromStringz is just return cString ? cString[0 .. strlen(cString)] : null; and all you'd have to do would be to replace strlen with wcslen from core.stdc.wchar_. There's a decent chance that you'll want to allocate the string though, in which case to!wstring would be the right choice. - Jonathan M Davis
Sep 05
parent John Burton <john.burton jbmail.com> writes:
On Tuesday, 5 September 2017 at 08:39:37 UTC, Jonathan M Davis 
wrote:
 On Tuesday, September 05, 2017 08:15:04 John Burton via 
 Digitalmars-d-learn wrote:
 std.string.fromStringz will create me a string from a null 
 terminated array of characters. But I have a zero terminated 
 array of "short"s (from a win32 api call) which I'd like to 
 turn into a wstring. But there doesn't seem to be a function 
 to do this.

 Do I need to write my own, or am I missing something?
I'm fairly certain that to!wstring will do it, but it will definitely allocate, whereas fromStringz just slices what it's given. I don't think that there's currently a wchar equivalent to fromStringz, but it would be pretty trivial to write if you didn't want to use to!wstring. fromStringz is just return cString ? cString[0 .. strlen(cString)] : null; and all you'd have to do would be to replace strlen with wcslen from core.stdc.wchar_. There's a decent chance that you'll want to allocate the string though, in which case to!wstring would be the right choice.
Thank you. I wanted something that didn't allocate in this case. The underlying storage will be kept for other reasons so I might as well have a string that just refers to the data contained in it. I had done something like you suggested, but wondered if I'd missed something given the existence of a function for byte strings.
Sep 05