Thanks a lot for the help.

Kind regards
André



On Thursday, 27 November 2014 at 17:29:50 UTC, Marc Schütz wrote:
On Thursday, 27 November 2014 at 16:08:13 UTC, Andre wrote:
Hi,

I implement a network protocol and use an Appender!(ubyte[])().
I have following issue. The first three bytes I have to fill,
the following bytes are reserved and must be 0. In this example
the overall header length must be 8.

import std.array: appender;
const HEADER_LENGTH = 8;
        
auto app = appender!(ubyte[])();
app.put(cast(ubyte)40);
app.put(cast(ubyte)5);
app.put(cast(ubyte)234);
// ... add 5 times 0
// variable length body will follow

In case of dynamic array I can simple set the length to 8.
Appender doesn't have a length attribute.

Is there some other nice D functionaliy I can use?
Maybe some functionality in std.array is missing: app.fill(0, HEADER_LENGTH)?
Currently I do a work around with a for loop.

Kind regards
André

You can initialize the appender with an existing array, or put an entire array into it at once:

    import std.array: appender;
    ubyte[] temp;
temp.reserve(8); // reserve first, so that only one allocation happens
    temp[0 .. 3] = [40, 5, 234];
    temp.length = 8;
    auto app = appender!(ubyte[])(temp);
    // or:
    app.put(temp);

The array will not be copied when the appender is constructed.

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