digitalmars.D.learn - arrays in DMD V2

steven kladitis (18/18) Apr 18 2014 import std.stdio;

Jesse Phillips (11/30) Apr 18 2014 First, don't use that syntax. everything should be placed on the

steven kladitis (8/44) Apr 18 2014 Thanks, I am trying to understand what I am doing. The docs seem

steven kladitis (42/42) Apr 18 2014 import std.stdio;

Jesse Phillips (12/54) Apr 18 2014 Works for me.

steven kladitis (64/64) Apr 19 2014 void main()

Jesse Phillips (4/26) Apr 19 2014 These are not the same [a3-a7], please double check what the
=?UTF-8?B?QWxpIMOHZWhyZWxp?= (19/20) Apr 19 2014 I think you are thinking in terms of C's syntax. Unlike C, array

steven kladitis (6/6) Apr 19 2014 Fantastic!!!!

=?UTF-8?B?QWxpIMOHZWhyZWxp?= (5/7) Apr 19 2014 They are all here:

=?UTF-8?B?QWxpIMOHZWhyZWxp?= (21/27) Apr 18 2014 I like to differentiate between arrays and associative arrays. Although

"steven kladitis" <steven_kladitis yahoo.com> writes:

import std.stdio;


void main()
{

int    a0[];
int    a1[][];
string a2[][];
string a3[][string];
string a4[][string][string];
//string a4[string][string][string]; is this the same as above????
int    a5[][string][string][string];
int    a6[string][int][string][float];
int    a7[int][int][string];

// how do you initialize each array, what type are they 
multidimensional???
// how do you define all of the above with limits on each 
dimension???



}

//help please

Apr 18 2014

"Jesse Phillips" <Jesse.K.Phillips+D gmail.com> writes:

On Saturday, 19 April 2014 at 00:27:32 UTC, steven kladitis wrote:
 import std.stdio;


 void main()
 {

 int    a0[];
 int    a1[][];
 string a2[][];
 string a3[][string];
 string a4[][string][string];
 //string a4[string][string][string]; is this the same as 
 above????
 int    a5[][string][string][string];
 int    a6[string][int][string][float];
 int    a7[int][int][string];

 // how do you initialize each array, what type are they 
 multidimensional???
 // how do you define all of the above with limits on each 
 dimension???
 }

 //help please

First, don't use that syntax. everything should be placed on the 
type:

Second,

void main() {
     int    a5[][string][string][string];
     pragma(msg, typeof(a5));
}

Third,

http://dlang.org/arrays.html
http://dlang.org/hash-map.html

Apr 18 2014

"steven kladitis" <steven_kladitis yahoo.com> writes:

Thanks, I am trying to understand what I am doing. The docs seem 
unclear to me on how to initialize these.  I think there are 
three ways.
  with brackets , the other with foreach or direct assignments.
-- here is a longer version
-- uncomment out the assignments to see the errors I get.
-- I am trying to understand arrays.



On Saturday, 19 April 2014 at 01:13:55 UTC, Jesse Phillips wrote:
 On Saturday, 19 April 2014 at 00:27:32 UTC, steven kladitis 
 wrote:
 import std.stdio;


 void main()
 {

 int    a0[];
 int    a1[][];
 string a2[][];
 string a3[][string];
 string a4[][string][string];
 //string a4[string][string][string]; is this the same as 
 above????
 int    a5[][string][string][string];
 int    a6[string][int][string][float];
 int    a7[int][int][string];

 // how do you initialize each array, what type are they 
 multidimensional???
 // how do you define all of the above with limits on each 
 dimension???
 }

 //help please

 First, don't use that syntax. everything should be placed on 
 the type:

 Second,

 void main() {
     int    a5[][string][string][string];
     pragma(msg, typeof(a5));
 }

 Third,

 http://dlang.org/arrays.html
 http://dlang.org/hash-map.html

Apr 18 2014

"steven kladitis" <steven_kladitis yahoo.com> writes:

import std.stdio;


void main()
{

int    a0[];
int    a1[][];
string a2[][];
string a3[][string];
string a4[][string][string];
//string a4[string][string][string]; is this the same as above????
int    a5[][string][string][string];
int    a6[string][int][string][float];
int    a7[int][int][string];

// how do you initialize each array, what type are they 
multidimensional???
// how do you define all of the above with limits on each 
dimension???

a0  = [1,2,3];
//writefln( a0 );

a1  = [ [ 1,2,3 ],[4,5,6]];
//writefln( a1 );

a2  = [ ["a","b" ],[ "c","d" ] ];

//writefln ( a2 );

//a3  = [ ["a","b" ],[ "c","d" ] ];
// does not work

//a4    = [ ["a","b" ];
// does not work.

//a5      = [ [1,"a","b"]];

   pragma(msg, typeof(a0));
    pragma(msg, typeof(a1));
     pragma(msg, typeof(a2));
      pragma(msg, typeof(a3));
       pragma(msg, typeof(a4));
        pragma(msg, typeof(a5));
         pragma(msg, typeof(a6));
          pragma(msg, typeof(a7));
//  does not work

//a6        = [ 1,["a",1,"b",4.0]];
// does not work


//a7 = [ 1,1,"a"];
// does not work


// also how would you do in a foreach?



}

Apr 18 2014

"Jesse Phillips" <Jesse.K.Phillips+D gmail.com> writes:

On Saturday, 19 April 2014 at 03:51:02 UTC, steven kladitis wrote:
 import std.stdio;


 void main()
 {

 int    a0[];
 int    a1[][];
 string a2[][];
 string a3[][string];
 string a4[][string][string];
 //string a4[string][string][string]; is this the same as 
 above????
 int    a5[][string][string][string];
 int    a6[string][int][string][float];
 int    a7[int][int][string];

 // how do you initialize each array, what type are they 
 multidimensional???
 // how do you define all of the above with limits on each 
 dimension???

 a0  = [1,2,3];
 //writefln( a0 );

 a1  = [ [ 1,2,3 ],[4,5,6]];
 //writefln( a1 );

 a2  = [ ["a","b" ],[ "c","d" ] ];

 //writefln ( a2 );

 //a3  = [ ["a","b" ],[ "c","d" ] ];
 // does not work

 //a4    = [ ["a","b" ];
 // does not work.

 //a5      = [ [1,"a","b"]];

   pragma(msg, typeof(a0));
    pragma(msg, typeof(a1));
     pragma(msg, typeof(a2));
      pragma(msg, typeof(a3));
       pragma(msg, typeof(a4));
        pragma(msg, typeof(a5));
         pragma(msg, typeof(a6));
          pragma(msg, typeof(a7));
 //  does not work

Works for me.

a6 = int[float][string][int][string]
a7 = int[string][int][int]


 //a6        = [ 1,["a",1,"b",4.0]];
 // does not work

a6 = ["a": [1: ["b": [4.0: 5]]]];
writeln(a6["a"]);

 //a7 = [ 1,1,"a"];
 // does not work

a7 = [1: [2: ["3": 4]]];

 // also how would you do in a foreach?

foreach is for getting values out.

a0 ~= 7 // Append 7 to array
int[string] a8;
a8["hello"] = 6; // Add six to a8 for "hello"
assert(a8["hello"] == 6);

Apr 18 2014

"steven kladitis" <steven_kladitis yahoo.com> writes:

void main()
{

//int    a0[];
int[] a0;
//int    a1[][];
int[][] a1;
//string a2[][];
string[][] a2;
//string a3[][string];
string[string] a3;
//  string[][string] a3;
// possibly should be above for a3
//string a4[][string][string];
string[][string][string] a4;
//string a4[string][string][string]; is this the same as above????
//int    a5[][string][string][string];
int[][string][string][string] a5;
//int    a6[string][int][string][float];
int[string][int][string][float] a6;
//int    a7[int][int][string];
int[int][int][string] a7;


// how do you initialize each array, what type are they 
multidimensional???
// how do you define all of the above with limits on each 
dimension???

a0  = [1,2,3];
// works
writeln( a0 );

a1  = [ [ 1,2,3 ],[4,5,6]];
// works
writeln( a1 );

a2  = [ ["a","b" ],[ "c","d" ] ];
//works
writeln ( a2 );

a3  = [ "a":"b","c":"d"];
// works
writeln ( a3 );

a4    = [ "a":["b":["c" ]]];
//works
writeln( a4 );

//a5    = [ 1 :["a":["b":["c" ]]]];
// does not work
writeln(a5);

//  pragma(msg, typeof(a0));
//  pragma(msg, typeof(a1));
//  pragma(msg, typeof(a2));
//  pragma(msg, typeof(a3));
//  pragma(msg, typeof(a4));
//  pragma(msg, typeof(a5));
//  pragma(msg, typeof(a6));
//  pragma(msg, typeof(a7));


//a6        = [ 1,["a",1,"b",4.0]];
// does not work
//a6 = ["a": [1: ["b": [4.0: 5]]]];
// does not work
writeln(a6);


//a7 = [ 1,1,"a"];
// does not work
//a7 = [1: 2[:"3"]];
// does not work
writeln(a7);


// in DMD 2.065
// not sure how to initialize 5,6,7



}

Apr 19 2014

"Jesse Phillips" <Jesse.K.Phillips+D gmail.com> writes:

On Saturday, 19 April 2014 at 16:14:45 UTC, steven kladitis wrote:
 void main()
 {

 //int    a0[];
 int[] a0;
 //int    a1[][];
 int[][] a1;
 //string a2[][];
 string[][] a2;
 //string a3[][string];
 string[string] a3;
 //  string[][string] a3;
 // possibly should be above for a3
 //string a4[][string][string];
 string[][string][string] a4;
 //string a4[string][string][string]; is this the same as 
 above????
 //int    a5[][string][string][string];
 int[][string][string][string] a5;
 //int    a6[string][int][string][float];
 int[string][int][string][float] a6;
 //int    a7[int][int][string];
 int[int][int][string] a7;

These are not the same [a3-a7], please double check what the 
pragma prints for your types and what you have written here for 
conversion.

Apr 19 2014

=?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:

On 04/19/2014 09:14 AM, steven kladitis wrote:

 // does not work

I think you are thinking in terms of C's syntax. Unlike C, array 
definition syntax is consistent in D.

I inserted spaces below to make it stand out:

     int[]  [string] arr;

The definition above is in the following form:

     ValueType[KeyType] arr;

So, it is an associative array of string keys and int[] values. If you 
think that way, the following program makes sense:

void main()
{
     int[][string][string][string] a5;
     int[string][int][string][float] a6;
     int[int][int][string] a7;

     a5 = [ "a" : [ "b" : [ "c" : [ 1 ] ] ] ];
     a6 = [ 1.0f : [ "a" : [ 1 : [ "b": 5 ] ] ] ];
     a7 = [ "a" : [ 1 : [ 2 : 3 ]]];
}

Ali

Apr 19 2014

"steven kladitis" <steven_kladitis yahoo.com> writes:

Fantastic!!!!

I am getting a much clearer picture of arrays!!!! I appreciate 
all of the help!!!!
I see many examples of D online, but most do not compile under 
2.065.  I am wondering if there is a D manual or book just for D 
V2.0.

Apr 19 2014

=?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:

On 04/19/2014 11:59 AM, steven kladitis wrote:

 I am getting a much clearer picture of arrays!!!!

Great! :)

 a D manual or book just for D V2.0.

They are all here:

   http://wiki.dlang.org/Books

Ali

Apr 19 2014

=?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:

On 04/18/2014 08:47 PM, steven kladitis wrote:
 Thanks, I am trying to understand what I am doing. The docs seem unclear
 to me on how to initialize these.  I think there are three ways.
   with brackets , the other with foreach or direct assignments.
 -- here is a longer version
 -- uncomment out the assignments to see the errors I get.
 -- I am trying to understand arrays.

I like to differentiate between arrays and associative arrays. Although 
its name has "array" in it, an associative arrays is actually a hash table.

First, let me repeat Jesse Phillips's suggestion: Do not use the C 
syntax. Here is the D syntax: T[N] means "an array of N objects of type T."

So, the following is an array of 2 ints:

     int[2] arr;

When the size of the array is specified like that, it is a fixed-length 
array.

There are dynamic arrays where the actual array is maintained and owned 
by the runtime. Such arrays are accessed by a slice. A slice is defined 
similar to a fixed-length array but the size is missing:

     int[] arr;

An associative array (AA) is defined by the syntax ValueType[KeyType]. 
So, the following is an AA mapping strings to doubles:

     double[string] table;

Here are three chapters on these topics:

   http://ddili.org/ders/d.en/arrays.html

   http://ddili.org/ders/d.en/slices.html

   http://ddili.org/ders/d.en/aa.html

Ali

Apr 18 2014

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digitalmars.D.learn - arrays in DMD V2