This is sample1.txt. It is intended to be included by sample.txt.
If you want to switch back to sample.txt, try the buttons on the
File List Bar (above this window).

// Let's put some C/C++ blocks here.
{
    // This is the outermost level
    {
        // This is level 1.
    }
    {
        // This is also level 1.
        {
            // This is level 2.
        }
    }
}

Try clicking on the nesting outlines on the left. This highlights
the block nesting you selected.

// Let's define some symbols here.
#define SYMBOL_100 100
#define SYMBOL_201 (4 * SYMBOL_100) / 2 + 1

// Let's put some C/C++ #if/#endif preprocessor directives here.
#if SYMBOL_100 < 50
// No. SYMBOL_100 is not smaller than 50.
#elif SYMBOL_100 > 100
// No. SYMBOL_100 is not bigger than 100.
#elif (4 * SYMBOL_100) / 2 + 1 == SYMBOL_201
// Yes. (4 * 100) / 2 + 1 == 201.
#else
// No. Not here.
#endif

Here is how to examine the value of a symbol, say SYMBOL_201:
Double-click here on SYMBOL_201 while holding down the Ctrl key will
bring up the symbol value modeless dialog box. In the dialog, you
should see the definition of SYMBOL_201, and it's value.

// Let's include sample2.txt here.
#include "sample2.txt"

The file sample2.txt included undefines SYMBOL_100. So, the value
of SYMBOL_100 here should be 0. Let's find out where exactly the
symbol is undefined:

1. Double-click here on SYMBOL_100 to select the word.
2. Bring up the right-mouse menu and select the menu item
   [Lookup At Line ...]. This will bring up the browse dialog box.
3. Uncheck the [At Line #] check box of the dialog box.
4. Click on the button [Go To Undefinition].

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