Gambas
Revision as of 21:32, 8 January 2006 by Woozle (talk | contribs) (→Stumbling Blocks: consolidation of event-handling notes; parameter parenthesization)
Gambas is a programming language and IDE.
Overview
- intended to fill the same niche as VB, though not intended to be code-compatible
- currently only available for Linux and other Unix-derivatives (there is a partially-functioning Windows version)
- open-source
Articles
Reference
Stumbling Blocks
- One of the more confusing aspects of Gambas (for a Visual Basic user, anyway) is that Gambas's events do not pass parameters; instead, you have to know where to fetch them from:
- Form resize: the size is easily available as a form property ("ME.")
- Mouse clicks: use the Mouse object
- Key presses: use the Key object
- Controls in a group: use the LAST keyword
- The most obvious solution would have been for the event to pass the control as a parameter; Gambas events don't seem to use parameters. Another intuitive solution would have been for the group itself to appear on the form's list of controls/methods, as an alias for the currently active/effective control. Finally, if the form had an ActiveControl property, I could pull the .Tag value from there, although I would expect to run into problems using this technique under some circumstances. Answer: The LAST keyword refers to the control which generated the current event.
- Another minor thing to remember is that Gambas subroutines always put parentheses around the parameter list (VB subroutines do not, unless the subroutine is a function or property and the return value is being retrieved).
Flaws
- (Minor) Identifiers are not automatically capitalized to match their declaration, as in VB; fortunately, identifiers are not case-sensitive, so this doesn't make things ugly the way it does in C/C++.
- (Semi-minor) The field-list doesn't pop up under certain circumstances; checking into this.
- (significant) Help system is not context-sensitive; you have to type the term in manually and search for it. Similarly, there doesn't seem to be a way to go to an identifier's definition.
- The field-list popup isn't smart in certain circumstances:
- Type me.controlname.field (use a real control name and a real field name)
- Move cursor somewhere else
- go back to same line, and highlight the "." between "controlname" and "field"
- type "."
- (minor) The list doesn't automatically select the field which was there already
- (annoying) When you select the field you want, it is inserted between "." and the fieldname that was there before. This follows logically from the editing rules, but is not what we want to happen; the selected fieldname should replace the old fieldname.
Notes
- The Help system appears to be wiki-based, possibly feeding directly off the Gambas wiki -- so any errors found can be corrected by anyone, in theory. Not sure how easy this is in practice. (Edit buttons do not appear in the Help app, so you would have to find the correct page on the wiki.)