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digitalmars.D.learn - Re: simple syntax issue with template

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 I'm trying to create 2 extra method for arrays ("range" would be
 better, though I don't quite understand what is a "range")
 Although I have some indecipherable (to me) compiler error...

 What's wrong with the code below?
 ==================
 import std.algorithm;

 public:

 void remove(T)(ref T[] array, T element)
 {
    auto index = array.countUntil!("a == b", T[], T)(array, element);
    removeAt(index);
 }

 void removeAt(T)(ref T[] array, sizediff_t index)
 {
    if(index < 0 || index >= array.length)
        return;
    array.replaceInPlace(index, index + 1, []);
 }


 unittest
 {
    auto a = [1, 3, 4];
    a.remove(3);
    assert(a == [1, 4]);
 }
 ======================



Hi Lloyd,

why not just use the built in functionality of arrays?

//----------------------
import std.stdio;

void main() {
    auto a = [1, 2, 3, 4, 5, 6, 7, 8];
    remove(a, 3);

    foreach (i; a) {
        write(i, " ");
    }
    writeln("");
}

void remove(T) (ref T[] myarray, int element) {
    auto front = myarray[0 .. (element -1)];
    auto back =  myarray[element .. $];
    myarray = front ~ back;
    // or simply: myarray = myarray[0 .. (element - 1)] ~ myarray[element ..
$];
}
//----------------------

Josh

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<meta charset=3D"utf-8"><span class=3D"Apple-style-span" style=3D"border-co=
llapse: collapse; font-family: arial, sans-serif; font-size: 13px; ">&gt; I=
&#39;m trying to create 2 extra method for arrays (&quot;range&quot; would =
be<br>
&gt; better, though I don&#39;t quite understand what is a &quot;range&quot=
;)<br>&gt; Although I have some indecipherable (to me) compiler error...<br=

&gt;<br>&gt; What&#39;s wrong with the code below?<br>&gt; =3D=3D=3D=3D=3D=



&gt; import std.algorithm;<br>&gt;<br>&gt; public:<br>&gt;<br>&gt; void rem=
ove(T)(ref T[] array, T element)<br>&gt; {<br>&gt; =A0 =A0auto index =3D ar=
ray.countUntil!(&quot;a =3D=3D b&quot;, T[], T)(array, element);<br>&gt; =
=A0 =A0removeAt(index);<br>
&gt; }<br>&gt;<br>&gt; void removeAt(T)(ref T[] array, sizediff_t index)<br=

&gt; {<br>&gt; =A0 =A0if(index &lt; 0 || index &gt;=3D array.length)<br>&g=



+ 1, []);<br>&gt; }<br>
&gt;<br>&gt;<br>&gt; unittest<br>&gt; {<br>&gt; =A0 =A0auto a =3D [1, 3, 4]=
;<br>&gt; =A0 =A0a.remove(3);<br>&gt; =A0 =A0assert(a =3D=3D [1, 4]);<br>&g=
t; }<br></span><span class=3D"Apple-style-span" style=3D"border-collapse: c=
ollapse; font-family: arial, sans-serif; font-size: 13px; ">&gt; =3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D</span><div>
<font class=3D"Apple-style-span" face=3D"arial, sans-serif"><span class=3D"=
Apple-style-span" style=3D"border-collapse: collapse;"><br></span></font></=
div><div><font class=3D"Apple-style-span" face=3D"arial, sans-serif"><span =
class=3D"Apple-style-span" style=3D"border-collapse: collapse;">Hi Lloyd,<b=
r>
</span></font></div><div><font class=3D"Apple-style-span" face=3D"arial, sa=
ns-serif"><span class=3D"Apple-style-span" style=3D"border-collapse: collap=
se;"><br></span></font></div><div><font class=3D"Apple-style-span" face=3D"=
arial, sans-serif"><span class=3D"Apple-style-span" style=3D"border-collaps=
e: collapse;">why not just use the built in functionality of arrays?=A0<br>
</span></font></div><div><font class=3D"Apple-style-span" face=3D"arial, sa=
ns-serif"><span class=3D"Apple-style-span" style=3D"border-collapse: collap=
se;"><br></span></font></div><div><font class=3D"Apple-style-span" face=3D"=
arial, sans-serif"><span class=3D"Apple-style-span" style=3D"border-collaps=
e: collapse;">//----------------------</span></font></div>
<div><font class=3D"Apple-style-span" face=3D"arial, sans-serif"><span clas=
s=3D"Apple-style-span" style=3D"border-collapse: collapse;"><div>import std=
.stdio;</div></span></font><span class=3D"Apple-style-span" style=3D"border=
-collapse: collapse; font-family: arial, sans-serif; ">=A0 =A0</span><font =
class=3D"Apple-style-span" face=3D"arial, sans-serif"><span class=3D"Apple-=
style-span" style=3D"border-collapse: collapse;"><div>
void main() {</div><div>=A0 =A0 auto a =3D [1, 2, 3, 4, 5, 6, 7, 8];</div><=
div>=A0 =A0 remove(a, 3);</div><div>=A0 =A0=A0</div><div>=A0 =A0 foreach (i=
; a) {</div><div>=A0 =A0 =A0 =A0 write(i, &quot; &quot;);</div><div>=A0 =A0=
 }</div><div>=A0 =A0 writeln(&quot;&quot;);</div>
<div>}</div><div><br></div><div>void remove(T) (ref T[] myarray, int elemen=
t) {</div><div>=A0 =A0 auto front =3D myarray[0 .. (element -1)];</div><div=

=A0 =A0 auto back =3D =A0myarray[element .. $];</div><div>=A0 =A0 myarray =



<div>=A0 =A0 // or simply: myarray =3D myarray[0 .. (element - 1)] ~ myarra=
y[element .. $];</div><div>}</div><div><meta charset=3D"utf-8">//----------=
------------</div><div><br></div><div>Josh</div></span></font></div>

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Jun 13 2011