Installation Technical Details

EXPL is available as a standard Windows installation program that handles all installation issues. The various files can also be installed manually. Here is a description of the installation process and relevant issues.

1. Installation Directories. Portions of the EXPL files are placed in several directories. Here is a description of each directory:

a. Install Directory. The Install Directory is the location where the main EXPL programs are installed. The default Install Directory is C:\EXPL. If the directory doesn't exist, the installation program creates it. This directory is used because the Program Files directory is treated as read-only under Vista and Win7.

b. Demo Directory. The demo directory holds EXPL demonstration programs that are included with the distribution of EXPL. The normal location for the demo programs is C:\EXPL\Demos.

c. Include Directory. By tradition dating back to the earliest versions of XPL on the PC, include files are placed in C:\CXPL. EXPL uses the same directory for the same purpose. The installation program normally installs the file EXPLCodes.xpl here, which contains the standard intrinsic declarations for EXPL.

d. Application Data. Certain application-specific files are stored in the Application Data directory. These are files that the operating system must find to integrate XPL with certain "shell" functions. This directory is in slightly different places under different versions of Windows:

Windows XP: C:\Documents and Settings\<user>\Application Data\xpl

Vista/Win7: C:\Users\<user>\AppData\Roaming

Currently, the program installs prototyp.xpl to this directory. This file is used by Windows to create a new empty XPL file if you right click in a folder and select the New option. This file contains an include declaration for EXPLCodes.xpl and an empty begin-end pair.

2. Installation Files. Here is a description of all the files that are normally installed with EXPL:

a. EmbedXpl.exe. This is the main program file for EXPL and the EXPL IDE. It is normally installed in the Install Directory described above.

b. XPLStub.exe. This file is the base unit for creating stand-alone XPL programs. It must be installed to the same directory as EmbedXpl.exe, otherwise the stand-alone program option will not work.

c. EmbedXPL.chm. This is the help file for EXPL. It must be installed in the same directory as EmbedXpl.exe, otherwise EXPL won't be able to find its help files.

d. Demos. The installation package contains 15 XPL demo programs. These programs are normally installed in the Demo Directory described above.

e. ProtoTyp.xpl. This file is an XPL prototype file that enables Windows to create an new XPL file when the user right clicks in any folder and selects the New option from the menu. For this option to work, several entries must be added to the Windows Registry. The installation program automatically adds these changes to the registry. The changes are described in detail below.

3. Registry Changes. The Installation program makes a number of changes to the Registry to integrate EXPL with the operating system. These changes aren't necessary to edit, compile, run or generate stand-alone XPL programs. They are only necessary for integrating EXPL with the operating system to:  

a. Associate the .XPL file extension with the class name "XPLSourceFile"

HKEY_CURRENT_USER\SOFTWARE\CLASSES\.xpl\"XPLSourceFile"

b. Associate the .XPL file extension with a prototype file to be used to generate a new XPL file from the standard Windows context menu for folders. Item "d" below is required for the New menu option to function properly.

HKEY_CURRENT_USER\SOFTWARE\CLASSES\.xpl\ShellNew\"<ApplicationData>\xpl\"prototyp.xpl"

c. Associate the "XPLSourceFile" class name with an exe file for the purpose of providing an icon to be displayed for XPL programs.

HKEY_CURRENT_USER\SOFTWARE\CLASSES\XPLSourceFile\DefaultIcon\"c:\EXPL\EmbedXPL.exe"

d. Associate "XPLSourceFile" class name with an exe file for the purpose of opening an XPL file when you double click on it.

HKEY_CURRENT_USER\Software\Classes\XPLSourceFile\Shell\Open\Command\"c:\EXPL\\EmbedXpl.exe "%1""

4. Filename Extensions. Although the installation program does associate EXPL with XPL files, it will not override a pre-existing file association. This means that if you have an editor or viewer already configured to open XPL files, the installation program will not associate the .XPL file extension with EXPL. This is because people who have been using XPL0 in the past, probably already have another program associated with the .XPL extension. If you want to associate the .XPL extension with EXPL, you can do it manually by right clicking on an XPL file and selecting the Open With option.