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  <div class="section" id="reflection-and-meta-programming">
<h1>Reflection and Meta-programming<a class="headerlink" href="#reflection-and-meta-programming" title="Permalink to this headline">¶</a></h1>
<p>Since the Ring programming language is a dynamic language, we can get answers about
the program code and we can modify our code during the runtime.</p>
<p>In this chapter we will learn about this and the available functions to use.</p>
<div class="section" id="locals-function">
<h2>locals() Function<a class="headerlink" href="#locals-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of variables names in the current scope using the locals() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>locals() --&gt; a list contains the variables names in the current scope
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>test(&quot;hello&quot;)

func test cMsg

        see cMsg + nl

        x = 10
        y = 20
        z = 30

        see locals()
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>hello
cmsg
x
y
z
</pre></div>
</div>
</div>
<div class="section" id="globals-function">
<h2>globals() Function<a class="headerlink" href="#globals-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of variables names in the global scope using the globals() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>globals() --&gt; a list contains variables names in the global scope
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>x=10 y=20 z=30
test()

func test
        see &quot;message from test()&quot; + nl +
            &quot;Global Variables:&quot; + nl
        see globals()
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>message from test()
Global Variables:
x
y
z
</pre></div>
</div>
</div>
<div class="section" id="functions-function">
<h2>functions() Function<a class="headerlink" href="#functions-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of functions names written in the Ring language using the functions() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>functions() --&gt; a list contains functions names
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see functions()

func f1
        see &quot;f1&quot; + nl

func f2
        see &quot;f2&quot; + nl

func f3
        see &quot;f3&quot; + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>f1
f2
f3
</pre></div>
</div>
</div>
<div class="section" id="cfunctions-function">
<h2>cfunctions() Function<a class="headerlink" href="#cfunctions-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of functions names written in the C language using the cfunctions() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>cfunctions() --&gt; a list contains functions names
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>aList =  cfunctions()
See &quot;Count : &quot; + len(aList) + nl
for x in aList
        see x + &quot;()&quot; + nl
next
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>Count : 186
len()
add()
del()
get()
clock()
...
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The complete list is removed from the previous output.</p>
</div>
</div>
<div class="section" id="islocal-function">
<h2>islocal() Function<a class="headerlink" href="#islocal-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a variable is defined in the local scope or not using the islocal() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>islocal(cVariableName) --&gt; returns 1 if the variable is defined in the local scope
                           returns 0 if the variable is not defined in the local scope
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>test()

func test
        x=10 y=20
        see islocal(&quot;x&quot;) + nl +
            islocal(&quot;y&quot;) + nl +
            islocal(&quot;z&quot;) + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
1
0
</pre></div>
</div>
</div>
<div class="section" id="isglobal-function">
<h2>isglobal() Function<a class="headerlink" href="#isglobal-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a variable is defined in the global scope or not using the isglobal() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isglobal(cVariableName) --&gt; returns 1 if the variable is defined in the global scope
                            returns 0 if the variable is not defined in the global scope
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>x=10 y=20

test()

func test
        see isglobal(&quot;x&quot;) + nl +
            isglobal(&quot;y&quot;) + nl +
            isglobal(&quot;z&quot;) + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
1
0
</pre></div>
</div>
</div>
<div class="section" id="isfunction-function">
<h2>isfunction() Function<a class="headerlink" href="#isfunction-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a Ring function is defined or not using the isfunction() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isfunction(cFunctionName) --&gt; returns 1 if the Ring function is defined
                              returns 0 if the Ring function is not defined
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see isfunction(&quot;f1&quot;) + nl +
    isfunction(&quot;f2&quot;) + nl +
    isfunction(&quot;f3&quot;) + nl

func f1
        see &quot;message from f1()&quot; + nl

func f2
        see &quot;message from f2()&quot; + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
1
0
</pre></div>
</div>
</div>
<div class="section" id="iscfunction-function">
<h2>iscfunction() Function<a class="headerlink" href="#iscfunction-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a C function is defined or not using the iscfunction() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>iscfunction(cFunctionName) --&gt; returns 1 if the C function is defined
                               returns 0 if the C function is not defined
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see iscfunction(&quot;len&quot;) + nl +
    iscfunction(&quot;add&quot;) + nl +
    iscfunction(&quot;test&quot;) + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
1
0
</pre></div>
</div>
</div>
<div class="section" id="packages-function">
<h2>packages() Function<a class="headerlink" href="#packages-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of packages names using the packages() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>packages() --&gt; a list contains packages names
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>See packages()

Package Package1
        Class class1
                Func f1

Package Package2
        Class class1
                Func f1

Package Package3
        Class class1
                Func f1

Package Package4
        Class class1
                Func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>package1
package2
package3
package4
</pre></div>
</div>
</div>
<div class="section" id="ispackage-function">
<h2>ispackage() Function<a class="headerlink" href="#ispackage-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a package is defined or not using the ispackage() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>ispackage(cPackageName) --&gt; returns 1 if the Package is defined
                            returns 0 if the Package is not defined
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>See ispackage(&quot;package1&quot;) + nl +
    ispackage(&quot;package4&quot;) + nl +
    ispackage(&quot;package5&quot;) + nl +
    ispackage(&quot;package3&quot;) + nl

Package Package1
        Class class1
                Func f1

Package Package2
        Class class1
                Func f1

Package Package3
        Class class1
                Func f1

Package Package4
        Class class1
                Func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
1
0
1
</pre></div>
</div>
</div>
<div class="section" id="classes-function">
<h2>classes() Function<a class="headerlink" href="#classes-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of classes names using the classes() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>classes() --&gt; a list contains classes names
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>See classes()

Class class1
        Func f1

Class class2
        Func f1

Class class3
        Func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>class1
class2
class3
</pre></div>
</div>
</div>
<div class="section" id="isclass-function">
<h2>isclass() Function<a class="headerlink" href="#isclass-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a class is defined or not using the isclass() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isclass(cClassName) --&gt;  returns 1 if the Class is defined
                         returns 0 if the Class is not defined
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see isclass(&quot;class4&quot;) + nl +
    isclass(&quot;class3&quot;) + nl +
    isclass(&quot;class2&quot;) + nl

Class class1
        func f1

class class2
        func f1

class class3
        func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>0
1
1
</pre></div>
</div>
</div>
<div class="section" id="packageclasses-function">
<h2>packageclasses() Function<a class="headerlink" href="#packageclasses-function" title="Permalink to this headline">¶</a></h2>
<p>We can get a list of classes names inside a package using the packageclasses() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>packageclasses(cPackageName) --&gt; a list contains classes names inside the package
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see &quot;classes in Package1&quot; + nl
see packageclasses(&quot;Package1&quot;)
see &quot;classes in Package2&quot; + nl
see packageclasses(&quot;Package2&quot;)

Package Package1
        Class class1
                Func f1

Package Package2
        Class class1
                Func f1
        Class class2
                Func f1
        Class class3
                func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>classes in Package1
class1
classes in Package2
class1
class2
class3
</pre></div>
</div>
</div>
<div class="section" id="ispackageclass-function">
<h2>ispackageclass() Function<a class="headerlink" href="#ispackageclass-function" title="Permalink to this headline">¶</a></h2>
<p>We can check if a class is defined inside package or not using the ispackageclass() function.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>ispackageclass(cPackageName,cClassName) --&gt;  returns 1 if the Class is defined
                                             returns 0 if the Class is not defined
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>see ispackageclass(&quot;package1&quot;,&quot;class1&quot;) + nl +
    ispackageclass(&quot;package1&quot;,&quot;class2&quot;) + nl +
    ispackageclass(&quot;package2&quot;,&quot;class1&quot;) + nl +
    ispackageclass(&quot;package2&quot;,&quot;class2&quot;) + nl

Package Package1
        Class class1
                Func f1

Package Package2
        Class class1
                Func f1
        Class class2
                Func f1
        Class class3
                func f1
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>1
0
1
1
</pre></div>
</div>
</div>
<div class="section" id="classname-function">
<h2>classname() Function<a class="headerlink" href="#classname-function" title="Permalink to this headline">¶</a></h2>
<p>We can know the class name of an object using the classname() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>classname(object) --&gt; Returns the object class name
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point
o2 = new rect

see classname(o1) + nl          # print point
see classname(o2) + nl          # print rect

class point
class rect
</pre></div>
</div>
</div>
<div class="section" id="objectid-function">
<h2>objectid() Function<a class="headerlink" href="#objectid-function" title="Permalink to this headline">¶</a></h2>
<p>We can know the object id using the objectid() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>objectid(object) --&gt; Returns the object id
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point
see objectid(o1) + nl
test(o1)

func test v
        see objectid(v) + nl

Class point x y z
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>021B5808
021B5808
</pre></div>
</div>
</div>
<div class="section" id="isobject-function">
<h2>isobject() Function<a class="headerlink" href="#isobject-function" title="Permalink to this headline">¶</a></h2>
<p>We can check the variable to know if it&#8217;s an object or not using the isobject() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isobject(variable) --&gt; Returns True if it&#39;s an object, False if it&#39;s not
</pre></div>
</div>
</div>
<div class="section" id="attributes-function">
<h2>attributes() Function<a class="headerlink" href="#attributes-function" title="Permalink to this headline">¶</a></h2>
<p>We can get the object attributes using the attributes() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>attributes(object) --&gt; Returns a list contains the object attributes
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point
aList = attributes(o1)          # we can use see attributes(o1)
for t in aList see t next       # print xyz
Class Point x y z
</pre></div>
</div>
</div>
<div class="section" id="methods-function">
<h2>methods() Function<a class="headerlink" href="#methods-function" title="Permalink to this headline">¶</a></h2>
<p>We can get the object methods using the methods() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>methods(object) --&gt; Returns a list contains the object methods
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new test
aList = methods(o1)

for x in aList
        cCode = &quot;o1.&quot;+x+&quot;()&quot;
        eval(cCode)
next

Class Test
        func f1
                see &quot;hello from f1&quot; + nl
        func f2
                see &quot;hello from f2&quot; + nl
        func f3
                see &quot;hello from f3&quot; + nl
        func f4
                see &quot;hello from f4&quot; + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>hello from f1
hello from f2
hello from f3
hello from f4
</pre></div>
</div>
</div>
<div class="section" id="isattribute-function">
<h2>isattribute() Function<a class="headerlink" href="#isattribute-function" title="Permalink to this headline">¶</a></h2>
<p>We can test if the object contains an attribute or not using the isattribute() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isattribute(object,cAttributeName) --&gt; Returns True if the object contains the attribute
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point

see isattribute(o1,&quot;x&quot;) + nl    # print 1
see isattribute(o1,&quot;t&quot;) + nl    # print 0
see isattribute(o1,&quot;y&quot;) + nl    # print 1
see isattribute(o1,&quot;z&quot;) + nl    # print 1

class point x y z
</pre></div>
</div>
</div>
<div class="section" id="isprivateattribute-function">
<h2>isprivateattribute() Function<a class="headerlink" href="#isprivateattribute-function" title="Permalink to this headline">¶</a></h2>
<p>We can test if the object contains a private attribute or not using the isprivateattribute() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isprivateattribute(object,cAttributeName) --&gt; Returns True if the object
                                              contains the private attribute
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new person

see isprivateattribute(o1,&quot;name&quot;) + nl +
    isprivateattribute(o1,&quot;address&quot;) + nl +
    isprivateattribute(o1,&quot;phone&quot;) + nl +
    isprivateattribute(o1,&quot;job&quot;) + nl +
    isprivateattribute(o1,&quot;salary&quot;)

Class Person
        name address phone
        private
                job salary
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>0
0
0
1
1
</pre></div>
</div>
</div>
<div class="section" id="ismethod-function">
<h2>ismethod() Function<a class="headerlink" href="#ismethod-function" title="Permalink to this headline">¶</a></h2>
<p>We can test if the object class contains a method or not using the ismethod() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>ismethod(object,cMethodName) --&gt; Returns True if the object class contains the method
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point

see ismethod(o1,&quot;print&quot;) + nl           # print 1

mylist = []
mylist + new point

see ismethod(mylist[1],&quot;print&quot;) + nl    # print 1

class point x y z
        func print
                see x + nl + y + nl + z + nl
</pre></div>
</div>
</div>
<div class="section" id="isprivatemethod-function">
<h2>isprivatemethod() Function<a class="headerlink" href="#isprivatemethod-function" title="Permalink to this headline">¶</a></h2>
<p>We can test if the object class contains a private method or not using the isprivatemethod() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>isprivatemethod(object,cMethodName) --&gt; Returns True if the object class contains
                                        the private method
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new Test

see isprivatemethod(o1,&quot;f1&quot;) + nl +
    isprivatemethod(o1,&quot;f2&quot;)

Class Test
        func  f1
                see &quot;message from f1()&quot; + nl
        private
                func f2
                        see &quot;message from f2()&quot; + nl
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>0
1
</pre></div>
</div>
</div>
<div class="section" id="addattribute-function">
<h2>addattribute() Function<a class="headerlink" href="#addattribute-function" title="Permalink to this headline">¶</a></h2>
<p>We can add an attribute (or a group of attributes) to the object state (not the class) using
the addattribute() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>AddAttribute(object,cAttributeName|aAttributesList)
</pre></div>
</div>
<p>Example(1):</p>
<div class="highlight-none"><div class="highlight"><pre>see new point {x=10 y=20 z=30}
Class Point
        AddAttribute(self,[&quot;x&quot;,&quot;y&quot;,&quot;z&quot;])
</pre></div>
</div>
<p>Example(2):</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point
addattribute(o1,&quot;x&quot;)
addattribute(o1,&quot;y&quot;)
addattribute(o1,&quot;z&quot;)
see o1 {x=10 y=20 z=30}
class point
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>x: 10.000000
y: 20.000000
z: 30.000000
</pre></div>
</div>
</div>
<div class="section" id="addmethod-function">
<h2>addmethod() Function<a class="headerlink" href="#addmethod-function" title="Permalink to this headline">¶</a></h2>
<p>We can add a method to the object class using the addmethod() function
This method can be used with any object from the same class.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>AddMethod(Object,cNewMethodName,cMethodName|AnonymousFunction)
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point { x=10 y=20 z=30 }

addmethod(o1,&quot;print&quot;, func { see x + nl + y + nl + z + nl } )

o1.print()

Class point
        x y z
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>10
20
30
</pre></div>
</div>
<p>Instead of using anonymous function to add new method to the class, we can use the function name</p>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point { x=10 y=20 z=30 }

myfunc = func { see x + nl + y + nl + z + nl }

addmethod(o1,&quot;print&quot;, myfunc )
addmethod(o1,&quot;display&quot;, myfunc )
addmethod(o1,&quot;show&quot;, myfunc )

o1.print()
o1.display()
o1.show()

Class point
        x y z
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>10
20
30
10
20
30
10
20
30
</pre></div>
</div>
<p>Since we add the method to the class, any object from that class can use this method</p>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point { x=10 y=20 z=30 }
o2 = new point { x=100 y=200 z=300 }
o3 = new point { x=50 y=150 z=250 }

addmethod(o1,&quot;print&quot;, func { see x + nl + y + nl + z + nl } )

o1.print()
o2.print()
o3.print()

Class point
        x y z
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>10
20
30
100
200
300
50
150
250
</pre></div>
</div>
</div>
<div class="section" id="getattribute-function">
<h2>getattribute() function<a class="headerlink" href="#getattribute-function" title="Permalink to this headline">¶</a></h2>
<p>We can get the object attribute value using the getattribute() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>GetAttribute(oObject,cAttributeName) ---&gt; Attribute Value
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new point

see getattribute(o1,&quot;name&quot;) + nl +
    getattribute(o1,&quot;x&quot;) + nl +
    getattribute(o1,&quot;y&quot;) + nl +
    getattribute(o1,&quot;z&quot;) + nl

Class Point
        x=10 y=20 z=30
        name = &quot;3D-Point&quot;
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>3D-Point
10
20
30
</pre></div>
</div>
</div>
<div class="section" id="setattribute-function">
<h2>setattribute() function<a class="headerlink" href="#setattribute-function" title="Permalink to this headline">¶</a></h2>
<p>We can set the object attribute value using the setattribute() function</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>SetAttribute(oObject,cAttributeName,Value)
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>o1 = new person
setattribute(o1,&quot;cName&quot;,&quot;Mahmoud&quot;)
setattribute(o1,&quot;nSalary&quot;,1000000)
setattribute(o1,&quot;aColors&quot;,[&quot;white&quot;,&quot;blue&quot;,&quot;yellow&quot;])

see o1
see o1.aColors

Class Person
        cName
        nSalary
        aColors
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>cname: Mahmoud
nsalary: 1000000.000000
acolors: List...
white
blue
yellow
</pre></div>
</div>
</div>
<div class="section" id="mergemethods-function">
<h2>mergemethods() Function<a class="headerlink" href="#mergemethods-function" title="Permalink to this headline">¶</a></h2>
<p>We can share methods between classes without inheritance using the MergeMethods() function</p>
<p>This function merge class methods to another class.</p>
<p>Syntax:</p>
<div class="highlight-none"><div class="highlight"><pre>MergeMethods(cClassNameDestination,cClassNameSource)
</pre></div>
</div>
<p>Example:</p>
<div class="highlight-none"><div class="highlight"><pre>mergemethods(&quot;count&quot;,&quot;share&quot;)
mergemethods(&quot;count2&quot;,&quot;share&quot;)

o1 = new count  { test() }
o1 = new count2 { test() }

Class Share
        func one
                see &quot;one&quot; + nl
        func two
                see &quot;two&quot; + nl
        func three
                see &quot;three&quot; + nl

Class Display
        Func printline
                see copy(&quot;*&quot;,20) + nl

Class Count from Display
        Func test
                printline()
                one()
                two()
                three()
                printline()

Class Count2 from Display
        Func test
                three()
                two()
                one()
                printline()
</pre></div>
</div>
<p>Output:</p>
<div class="highlight-none"><div class="highlight"><pre>********************
one
two
three
********************
three
two
one
********************
</pre></div>
</div>
</div>
</div>


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  <h3><a href="index.html">Table Of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#">Reflection and Meta-programming</a><ul>
<li><a class="reference internal" href="#locals-function">locals() Function</a></li>
<li><a class="reference internal" href="#globals-function">globals() Function</a></li>
<li><a class="reference internal" href="#functions-function">functions() Function</a></li>
<li><a class="reference internal" href="#cfunctions-function">cfunctions() Function</a></li>
<li><a class="reference internal" href="#islocal-function">islocal() Function</a></li>
<li><a class="reference internal" href="#isglobal-function">isglobal() Function</a></li>
<li><a class="reference internal" href="#isfunction-function">isfunction() Function</a></li>
<li><a class="reference internal" href="#iscfunction-function">iscfunction() Function</a></li>
<li><a class="reference internal" href="#packages-function">packages() Function</a></li>
<li><a class="reference internal" href="#ispackage-function">ispackage() Function</a></li>
<li><a class="reference internal" href="#classes-function">classes() Function</a></li>
<li><a class="reference internal" href="#isclass-function">isclass() Function</a></li>
<li><a class="reference internal" href="#packageclasses-function">packageclasses() Function</a></li>
<li><a class="reference internal" href="#ispackageclass-function">ispackageclass() Function</a></li>
<li><a class="reference internal" href="#classname-function">classname() Function</a></li>
<li><a class="reference internal" href="#objectid-function">objectid() Function</a></li>
<li><a class="reference internal" href="#isobject-function">isobject() Function</a></li>
<li><a class="reference internal" href="#attributes-function">attributes() Function</a></li>
<li><a class="reference internal" href="#methods-function">methods() Function</a></li>
<li><a class="reference internal" href="#isattribute-function">isattribute() Function</a></li>
<li><a class="reference internal" href="#isprivateattribute-function">isprivateattribute() Function</a></li>
<li><a class="reference internal" href="#ismethod-function">ismethod() Function</a></li>
<li><a class="reference internal" href="#isprivatemethod-function">isprivatemethod() Function</a></li>
<li><a class="reference internal" href="#addattribute-function">addattribute() Function</a></li>
<li><a class="reference internal" href="#addmethod-function">addmethod() Function</a></li>
<li><a class="reference internal" href="#getattribute-function">getattribute() function</a></li>
<li><a class="reference internal" href="#setattribute-function">setattribute() function</a></li>
<li><a class="reference internal" href="#mergemethods-function">mergemethods() Function</a></li>
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