questions about conventions for GUI preferences

[John W. Eaton]

In some cases, the names and default values of GUI preferences are 
defined as symbolic constants in header files.  For example, in 
gui-preferences-ws.h:

  const gui_pref
  ws_hide_tool_tips ("workspaceview/hide_tools_tips", QVariant (false));

In a few recent changesets, I tried to use these symbolic names that are 
already defined in a consistent way.  I noticed a case where the key 
name was used as the default value and another where the identifier for 
a font size was used where a font name should have been.  I also spotted 
an incorrect use of a literal preference key.

We also have many literal character strings used for preference keys.  I 
came up with the attached list.

I saw (and fixed) at least one case where we had a symbolic constant 
defined with a key name and default value but the default value was 
repeated literally in the code so changing the value in the symbolic 
constant wouldn't have had any effect.  Having constants defined in 
multiple places seems bad to me.

It also seems odd that we would have (for exmample) a symbolic name for 
the variable editor font size but not the font name.  Why?

Should we try to define and use constants for all preference keys and 
default values, use literal strings everywhere, or some mixture as we 
have now?

With symbolic constants, it's harder to have typos in the strings used 
in various locations.

With symbolic constants, it's easier to know exactly what the key is 
without having to search but it's harder to ensure that there aren't any 
typos in the names and harder to change the name of a key.  Not that it 
matters too much, because it is already hard to change the name if you 
want to preserve backward compatibility with preference files from 
previous versions.

Comments?

jwe

prefs.txt
Description: Text document