Re: Insert array into an AA
On Thu, 18 Aug 2011 06:47:32 -0400, nrgyzer nrgy...@gmail.com wrote:
== Auszug aus Robert Clipsham (rob...@octarineparrot.com)'s Artikel
On 16/08/2011 20:17, nrgyzer wrote:
Hi everyone,
I've the following:
private static ubyte[][2][hash_t] classInstances;
this() {
classInstances[toHash()] = new ubyte[2]; // does not work
}
I want insert every class instance into the hashmap. Every class
instance should be contained in the map after the constructor was
called. When I compile my code, I get Error: cannot implicitly
convert expression (new ubyte[](2u)) of type ubyte[] to ubyte[][]
which is logical. But is there any way to insert every instance into
the array and define the array/map for this entry?
Thanks in advance!
Is there any particular reason you're using ubyte[][2][hash_t] there? To
keep a reference to each instance simply use:
class MyClass {
static MyClass[] classInstances;
this() {
classInstances ~= this;
}
}
If you in fact want to have a hashmap indexed by the instances with
values of type ubyte[][2], you can do this:
class MyClass {
static ubyte[][2][MyClass] classInstances;
this() {
classInstances[this] = new ubyte[][2];
}
}
The problem in your original code is that you were using = new ubyte[2]
rather than = new ubyte[][2]. Hope this helps.
Ok, that works - thx.
@Steve: I'll delete the entries from the map, but what's about
overriding the toHash()-function and return a simply int value?
If two instances return the same hash value (as is easily possible, but
maybe not for your context), then a collision occurs. Then opCmp is used
to determine if they are actually identical.
If you use hash_t as your key, then only one object is stored in the map,
the other is simply overwritten.
I also need this map-structure for further steps in my application. I's
possible to change it to
ubyte[][hash_t] classInstancesOne; // or ubyte[][MyClass]
ubyte[][hash_t] classInstancesTwo; // or ubyte[][MyClass]
but I thought one map for the same sense is better.
ubyte[][Object] should work for all class types.
Btw: I've two classes where one inherits:
class MyClassOne {
protected {
static __gshared {
uint counter;
uint[MyClassOne] fixedData;
}
uint otherData;
this(uint d) {
otherData = d;
}
}
this() {
fixedData[this] = ++counter;
}
@property ref {
uint myPropOne() { return fixedData[this]; }
uint myPropTwo() { return otherData; }
}
}
class MyClassTwo : MyClassOne {
shared(MyClassOne) supInstance;
this(uint d, MyClassOne mco) {
super(d);
supInstance = mco;
}
override ref alias supInstance.myPropOne myPropOne;
}
When I create an instance of MyClassOne and call myPropOne on it, I get
1. When I'm using this instance to create an instance of
MyClassTwo and call myPropOne, I get 0. Is there anything I'm doing
wrong?
That crazy override ref alias line, I have no idea what you're doing
there. For sure, override ref is not needed.
I'm surprised all of this compiles.
What I'm trying to do is: One super-class which contains some fixed data
(not inheritable) and some data which are different for each
class.
Note that protected does not prevent MyClassTwo from changing it.
Also note that even though you've only created one instance of MyClassOne,
every MyClassTwo instance is a MyClassOne (and calls MyClassOne's
constructor). I think you have applied the wrong techniques to solving
your design. Without knowing further your design/context, I can't really
help.
-Steve
Re: Insert array into an AA
== Auszug aus Steven Schveighoffer (schvei...@yahoo.com)'s Artikel
On Thu, 18 Aug 2011 06:47:32 -0400, nrgyzer nrgy...@gmail.com
wrote:
== Auszug aus Robert Clipsham (rob...@octarineparrot.com)'s
Artikel
On 16/08/2011 20:17, nrgyzer wrote:
Hi everyone,
I've the following:
private static ubyte[][2][hash_t] classInstances;
this() {
classInstances[toHash()] = new ubyte[2]; // does not work
}
I want insert every class instance into the hashmap. Every
class
instance should be contained in the map after the constructor
was
called. When I compile my code, I get Error: cannot implicitly
convert expression (new ubyte[](2u)) of type ubyte[] to ubyte[]
[]
which is logical. But is there any way to insert every
instance into
the array and define the array/map for this entry?
Thanks in advance!
Is there any particular reason you're using ubyte[][2][hash_t]
there? To
keep a reference to each instance simply use:
class MyClass {
static MyClass[] classInstances;
this() {
classInstances ~= this;
}
}
If you in fact want to have a hashmap indexed by the instances
with
values of type ubyte[][2], you can do this:
class MyClass {
static ubyte[][2][MyClass] classInstances;
this() {
classInstances[this] = new ubyte[][2];
}
}
The problem in your original code is that you were using = new
ubyte[2]
rather than = new ubyte[][2]. Hope this helps.
Ok, that works - thx.
@Steve: I'll delete the entries from the map, but what's about
overriding the toHash()-function and return a simply int value?
If two instances return the same hash value (as is easily possible,
but
maybe not for your context), then a collision occurs. Then opCmp
is used
to determine if they are actually identical.
If you use hash_t as your key, then only one object is stored in
the map,
the other is simply overwritten.
I also need this map-structure for further steps in my
application. I's
possible to change it to
ubyte[][hash_t] classInstancesOne; // or ubyte[][MyClass]
ubyte[][hash_t] classInstancesTwo; // or ubyte[][MyClass]
but I thought one map for the same sense is better.
ubyte[][Object] should work for all class types.
Btw: I've two classes where one inherits:
class MyClassOne {
protected {
static __gshared {
uint counter;
uint[MyClassOne] fixedData;
}
uint otherData;
this(uint d) {
otherData = d;
}
}
this() {
fixedData[this] = ++counter;
}
@property ref {
uint myPropOne() { return fixedData[this]; }
uint myPropTwo() { return otherData; }
}
}
class MyClassTwo : MyClassOne {
shared(MyClassOne) supInstance;
this(uint d, MyClassOne mco) {
super(d);
supInstance = mco;
}
override ref alias supInstance.myPropOne myPropOne;
}
When I create an instance of MyClassOne and call myPropOne on it,
I get
1. When I'm using this instance to create an instance of
MyClassTwo and call myPropOne, I get 0. Is there anything I'm
doing
wrong?
That crazy override ref alias line, I have no idea what you're doing
there. For sure, override ref is not needed.
I'm surprised all of this compiles.
What I'm trying to do is: One super-class which contains some
fixed data
(not inheritable) and some data which are different for each
class.
Note that protected does not prevent MyClassTwo from changing it.
Also note that even though you've only created one instance of
MyClassOne,
every MyClassTwo instance is a MyClassOne (and calls MyClassOne's
constructor). I think you have applied the wrong techniques to
solving
your design. Without knowing further your design/context, I can't
really
help.
-Steve
I'm working on a game where the player can build different buildings.
There are some general building-structures which defines the costs to
build it and some other things, but the name of each building can be
modified by the player. So, each building can have it's own name, but
the costs to build are always the same for each building.
To prevent the redefinition of all the property-methods, I want
redirect the properties of a simple building-property to it's
building structure. For example:
class BuildingShell {
private float[BuildingShell] pCostsToBuild;
protected {
string pName;
this(string name) {
pName = name;
}
}
this(string name, float costs) {
pName = name;
pCostsToBuild[this] = costs;
}
@property {
ref float costsToBuild() { return pCostsToBuild[this]; }
string name() { return pName; }
}
}
class Building : BuildingShell {
shared(BuildingShell) pShell;
this(BuldingShell bs, string name) {
super(name);
pShell = cast(shared) bs;
}
override @property
Re: Insert array into an AA
== Auszug aus Robert Clipsham (rob...@octarineparrot.com)'s Artikel
On 16/08/2011 20:17, nrgyzer wrote:
Hi everyone,
I've the following:
private static ubyte[][2][hash_t] classInstances;
this() {
classInstances[toHash()] = new ubyte[2]; // does not work
}
I want insert every class instance into the hashmap. Every class
instance should be contained in the map after the constructor was
called. When I compile my code, I get Error: cannot implicitly
convert expression (new ubyte[](2u)) of type ubyte[] to ubyte[][]
which is logical. But is there any way to insert every instance into
the array and define the array/map for this entry?
Thanks in advance!
Is there any particular reason you're using ubyte[][2][hash_t] there? To
keep a reference to each instance simply use:
class MyClass {
static MyClass[] classInstances;
this() {
classInstances ~= this;
}
}
If you in fact want to have a hashmap indexed by the instances with
values of type ubyte[][2], you can do this:
class MyClass {
static ubyte[][2][MyClass] classInstances;
this() {
classInstances[this] = new ubyte[][2];
}
}
The problem in your original code is that you were using = new ubyte[2]
rather than = new ubyte[][2]. Hope this helps.
Ok, that works - thx.
@Steve: I'll delete the entries from the map, but what's about overriding the
toHash()-function and return a simply int value?
I also need this map-structure for further steps in my application. I's
possible to change it to
ubyte[][hash_t] classInstancesOne; // or ubyte[][MyClass]
ubyte[][hash_t] classInstancesTwo; // or ubyte[][MyClass]
but I thought one map for the same sense is better.
Btw: I've two classes where one inherits:
class MyClassOne {
protected {
static __gshared {
uint counter;
uint[MyClassOne] fixedData;
}
uint otherData;
this(uint d) {
otherData = d;
}
}
this() {
fixedData[this] = ++counter;
}
@property ref {
uint myPropOne() { return fixedData[this]; }
uint myPropTwo() { return otherData; }
}
}
class MyClassTwo : MyClassOne {
shared(MyClassOne) supInstance;
this(uint d, MyClassOne mco) {
super(d);
supInstance = mco;
}
override ref alias supInstance.myPropOne myPropOne;
}
When I create an instance of MyClassOne and call myPropOne on it, I get 1.
When I'm using this instance to create an instance of
MyClassTwo and call myPropOne, I get 0. Is there anything I'm doing wrong?
What I'm trying to do is: One super-class which contains some fixed data (not
inheritable) and some data which are different for each
class.
Re: Insert array into an AA
On Tue, 16 Aug 2011 15:17:33 -0400, nrgyzer nrgy...@gmail.com wrote:
Hi everyone,
I've the following:
private static ubyte[][2][hash_t] classInstances;
this() {
classInstances[toHash()] = new ubyte[2]; // does not work
}
I want insert every class instance into the hashmap. Every class
instance should be contained in the map after the constructor was
called. When I compile my code, I get Error: cannot implicitly
convert expression (new ubyte[](2u)) of type ubyte[] to ubyte[][]
which is logical. But is there any way to insert every instance into
the array and define the array/map for this entry?
It's inadvisable to do this, unless you plan on manually deleting the
instances.
The reason is because the hash will maintain a pointer to every class
instance, which means the GC will never collect them.
Also, it's hard to know why you selected that type, but changing
classInstances to ubyte[][hash_t] should work.
Also, you don't need hash_t, you should be able to do ubyte[][Object]
classInstances.
then add like:
classInstances[this] = new ubyte[2];
The call to toHash is implicit.
-Steve
Re: Insert array into an AA
On 16/08/2011 20:17, nrgyzer wrote:
Hi everyone,
I've the following:
private static ubyte[][2][hash_t] classInstances;
this() {
classInstances[toHash()] = new ubyte[2]; // does not work
}
I want insert every class instance into the hashmap. Every class
instance should be contained in the map after the constructor was
called. When I compile my code, I get Error: cannot implicitly
convert expression (new ubyte[](2u)) of type ubyte[] to ubyte[][]
which is logical. But is there any way to insert every instance into
the array and define the array/map for this entry?
Thanks in advance!
Is there any particular reason you're using ubyte[][2][hash_t] there? To
keep a reference to each instance simply use:
class MyClass {
static MyClass[] classInstances;
this() {
classInstances ~= this;
}
}
If you in fact want to have a hashmap indexed by the instances with
values of type ubyte[][2], you can do this:
class MyClass {
static ubyte[][2][MyClass] classInstances;
this() {
classInstances[this] = new ubyte[][2];
}
}
The problem in your original code is that you were using = new ubyte[2]
rather than = new ubyte[][2]. Hope this helps.
--
Robert
http://octarineparrot.com/
