idlwave-extra-help-function

idlwave-extra-help-function is a variable defined in `idlw-help.el'.
Its value is

idlwave-help-with-source

• This variable may be risky if used as a file-local variable.

Documentation:
The function to call for online help if the normal help fails.
Online help works only for system routines which are described in the
IDL manuals. A function may be specified to access help from other sources.

The function must accept four arguments: NAME, TYPE, CLASS, KEYWORD.
The Help buffer is current when this function is called, and the help
text should be loaded into this buffer. If help is found, the
function should return the buffer position which should be used as
`window-start' in the help window. Also, the variable
`idlwave-help-mode-line-indicator' should be set to a useful string,
which will be displayed in the mode line of the help window. If
should also set the variable `idlwave-help-min-frame-width' to a
positive integer. IDLWAVE will ensure that the help frame is at least
that many columns wide. Failure to find help should be indicated by
throwing an error.

When this variable is non-nil, IDLWAVE will allow the mouse-3 help click
for every routine and keyword, even though the item may not be highlighted
in blue (indicating the availability of system documentation).

The default value for this function is `idlwave-help-with-source' which
loads the routine source file into the help buffer. If you try to write
a different function which accesses a special help file or so, it is
probably a good idea to still call this function as a fallback.

You can customize this variable.