Skip to content

Initialising an EWC session

Once you have a folder on your machine containing EWC, you can load it into a Dyalog APL session (18.2 or later is required):

]link.import # /path/to/ewc

Where /path/to/ewc is the name of the folder that you created during installation.

EWC.Init

The function EWC.Init takes a right argument of the mode that you want to enable:

  • 'Desktop' to run each form in an HTMLRenderer
  • 'Browser' to allow a single session from a browser
  • 'Multi' to allow multiple sessions from browsers (more about that later)

For example:

EWC.Init 'Desktop'

EWC.Init will also create cover-functions eWC, eWS and so on, in the namespace from which Init was called. These are intended to be used as replacements for the system functions ⎕WC, ⎕WS, etc.

If you would like to use a different prefix letter for these functions, you can provide a left argument to change the names. For example:

'x' EWC.Init 'Browser'

Will create functions xWC, xWS etc, and start EWC in Browser mode.

EWC.NOIDQ

If you want to experiment interactively, rather than call eDQ, you must set EWC.NOIDQ←0 to allow "Interactive DQ" (apologies for the negative switch name) before creating objects. This will probably change soon.

'Multi' Mode

In Desktop and Browser mode, your application can call EWC.Init and then immediately continue to create GUI components using eWC. In browser mode, EWC.Init will not return until a browser is connected.

However, in Multi mode, your application namespace must contain a function called Initialise which will be called when each new browser session starts, to create the GUI for the new session.

If your application namespace contains a function called onClose, then it will be called when the browser session is terminated.

Note that in Multi mode, the only permitted prefix is 'e'.