polserver/testsuite/escript/classes/this-reassignment.src

// Tests with modifying `this` in the constructor.
// We should never see `uninit` in the output.

class BaseClass()
  function BaseClass( this )
    print( $"BaseClass::BaseClass this={this}" );
  endfunction
endclass

// Call super() before modifying this
class Foo1( BaseClass )
  function Foo1( this )
    print( $"Foo1::Foo1 this={this}" );
    super();
    this := uninit;
    print( $"Foo1::Foo1 this={this}" );
  endfunction
endclass

var f1 := Foo1();
print( f1 );
print( "----" );

// Call super() after modifying this
class Foo2( BaseClass )
  function Foo2( this )
    print( $"Foo2::Foo2 this={this}" );
    this := uninit;
    super();
    print( this );
  endfunction
endclass

var f2 := Foo2();
print( f2 );

print( "----" );

// As usual, we can re-assign the variable that _holds_ a class instance.
f2 := "abc";
print( f2 );