Reflection/List properties: Difference between revisions

=={{header|C sharp}}==

{{works with|C sharp|7}}

using System.Collections.Generic;

using System.Linq;

}

 

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<pre>

 

=={{header|D}}==

 

struct S {

printProperties!S;

printProperties!C;

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<pre>Properties of S:

Properties of C:

b</pre>

 

=={{header|Elena}}==

import system'dynamic;

import extensions;

class MyClass

{

}

public program()

{

this Y := "String";

};

{

}

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<pre>

=={{header|Factor}}==

Mirrors present an object's slots and slot values as an associative structure.

 

TUPLE: foo

 

"apple" "banana" 200 <foo> <mirror>

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<pre>

 

=={{header|Go}}==

 

import (

}

fmt.Println()

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<pre>

=={{header|Groovy}}==

{{trans|Java}}

 

@SuppressWarnings("unused")

}

}

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<pre>All public fields (including inherited):

 

=={{header|Java}}==

 

public class ListFields {

}

}

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<pre>

There are multiple ways of getting property names, each of which include different subsets of an object's properties, such as enumerable or inherited properties. Properties in JavaScript can be enumerable or non-enumerable; enumerable properties are accessable when looping over the object with <code>for</code>. <code>Object.getOwnPropertyNames()</code>.

 

name: 'proto',

proto: true,

Object.entries(obj);

//[["name", "obj"], ["obj", true], ["doStuff", function()]]

 

=={{header|Julia}}==

{{works with|Julia|0.6}}

 

println("\nObject: $obj\nDescription:")

dump(obj)

 

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=={{header|Kotlin}}==

 

import kotlin.reflect.full.memberProperties

println("${prop.name.padEnd(13)} -> ${prop.get(example)}")

}

 

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=={{header|Lingo}}==

obj.foo = 23

obj.bar = 42

repeat with i = 1 to cnt

put obj.getPropAt(i)&" = "&obj[i]

 

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=={{header|Lua}}==

b = 2.0

c = "hello world"

listProperties(_G)

print("Package properties")

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<pre>Global properties

 

=={{header|Nanoquery}}==

class Fields

declare static field1 = "this is a static field. it will not be listed"

for fieldname in Fields.getFieldNames()

println fieldname

 

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field2

field4</pre>

 

=={{header|Objective-C}}==

#import <objc/runtime.h>

 

 

return 0;

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<pre>

 

Many of these options are also supported by other REXX implementations.

/* test values */

d.1=''

Say ol

End

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<pre> A B I L M N O S U V W X 9 datatype(v)

=={{header|Perl}}==

In Perl's bare-bones native OO system, an object is sometimes nothing more than a hash blessed into a class. It's properties could be simply listed by iterating over the keys. However more complex data structures can be present, so the safest option is always to use <code>Data::Dumper</code> to examine an object.

package Point;

use Class::Spiffy -base;

say Dumper $p1;

say Dumper $c1;

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<pre>$VAR1 = bless( {

 

=={{header|Phix}}==

Needs 0.8.1+

Note that content from and parameters to get_struct_type/fields() may change between releases.<br>

You should certainly be prepared for them to return NULL for unrecognised field names and types.<br>

Technically the code below is re-fetching tid and flags before returning them in a textual format.

 

 

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<pre>

 

=={{header|PHP}}==

class Foo {

}

 

var_dump(get_object_vars($obj));

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<pre>

}

</pre>

 

=={{header|PL/I}}==

 

Here we find the properties of a <code>[DateTime]</code> object:

Get-Date | Get-Member -MemberType Property

 

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The "Add" methods of a <code>[DateTime]</code> object:

Get-Date | Get-Member -MemberType Method -Name Add*

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The <code>[https://docs.python.org/3.5/library/functions.html#dir dir()]</code> function and Python's <code>[https://docs.python.org/3.5/library/inspect.html#module-inspect inspect]</code> module both will list properties.

 

__priv = 'private'

inspect.getmembers(chld)

#[('__class__', <class '__main__.Child'>), ..., ('args', (0, 'I', 'two')), ('args_bleh', "(0, 'I', 'two') bleh"), ('doNothing', <bound method Child.doNothing of Child(chld, 0, 'I', 'two')>), ('doStuff', <bound method Child.doStuff of Child(chld, 0, 'I', 'two')>), ('name', 'chld'), ('name_bleh', 'chld bleh'), ('own', "chld's own"), ('own_bleh', "chld's own bleh"), ('reBleh', <_sre.SRE_Pattern object at 0x10067bd20>), ('reBleh_bleh', '<_sre.SRE_Pattern object at 0x10067bd20> bleh')]

 

=={{header|Raku}}==

Each is represented as an <tt>Attribute</tt> object that contains a bunch of info:

 

has $!a = now;

has Str $.b;

for $object.^attributes {

say join ", ", .name, .readonly, .container.^name, .get_value($object);

 

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A simplistic example:

abc.j= -4.12

 

 

<br><br>

===version 2===

/* put_data2('a.') to show all a.tail values isn't that easy :-) */

j=2

put_data:

Parse Arg variable

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<pre>abc.2='-4.12'

 

=={{header|Ruby}}==

@@xyz = nil

def initialize(name, age)

p Foo.class_variable_get(:@@xyz) #=> :xyz

p Foo.class_variable_set(:@@abc, 123) #=> 123

 

=={{header|Scala}}==

===Java Interoperability===

{{Out}}Best seen running in your browser [https://scastie.scala-lang.org/MdkPxH6yTlS4W8TaXYxSgA Scastie (remote JVM)].

private val obj = new {

val examplePublicField: Int = 42

println("\nAll declared fields (excluding inherited):")

clazz.getDeclaredFields.foreach(f => println(s"${f}}"))

 

=={{header|Tcl}}==

 

For objects supporting this protocol, you can list all options by invoking the <tt>configure</tt> method without arguments (result split over multiple lines for readability):

8.6.5

% . configure

{-highlightcolor highlightColor HighlightColor #000000 #000000}

{-highlightthickness highlightThickness HighlightThickness 0 0} {-padx padX Pad 0 0} {-pady padY Pad 0 0}

 

Two-element sublists (eg <tt>-bd -borderwidth</tt>) represent aliases, and five-element sublists are of the form <tt>{optionName dbName dbClass defaultValue currentValue}</tt>. <tt>dbName</tt> and <tt>dbClass</tt> are related to how the option is specified in the <i>option database</i>.

Simply listing the option names is like this:

 

-borderwidth -class -menu -relief -screen -use -background -colormap -container -cursor -height

 

=={{header|Visual Basic .NET}}==

{{trans|C#}}

 

Module Module1

End Sub

 

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<pre>{ Name = PublicNumber, Value = 4 }

{ Name = _PublicNumber, Value = 4 }

{ Name = _PrivateNumber, Value = 2 }</pre>

 

=={{header|zkl}}==

 

Every object has a "properties" method, which returns a list of property names [for that object].

properties.println();

List(1,2,3).property(properties[0]).println(); // get value

List(1,2,3).Property(properties[0])().println(); // method that gets value

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<pre>