Feature Ideas: what changed

Revision 2 to 3. Removed lines have a minus sign; added lines have a plus sign.

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1	1		> Warning: This page is intended to collect ideas for features that could be included in FPC/Lazarus. Putting an idea here does not mean it WILL be put into FPC/Lazarus. It's just a place to gather ideas. Think of this as more of a wishlist.
2	2
3	3		If it is clear who is going to implement the feature, for example, because you have a patch or somebody on the mailing list volunteered to implement it, then it can be added to the [FPC/Lazarus Bugtracker](http://bugs.freepascal.org/), so it can be tracked and scheduled for a release.
4	4
5	5		If you really want to see a feature implemented urgently, have a look at [[Bounties]] to pay for development.
6	6
7	7		Tags: Wish, Wishes, Wishlist
8	8
9	9		# IDE
10	10
11	11		Features that could be included in the IDE
12	12
13	13		## An Integrated IDE
14	14
15	15		(Partly) done in 0.9.29: see [[Anchor Docking]]
16	16
17	17		> Warning: There are known bugs in the docking implementation. The Lazarus developers are aware of these and will be working on them if time permits. If you want to help speed this up by providing code, please get in touch on the Lazarus mailing list
18	18
19	19		There are too many windows in the IDE. The more features you use the more they pile up on your desktop and become hidden behind other windows. This is confusing for the newbie and otherwise a mess. Docking windows as found in some IDEs might seem to give flexibility however in practice it is a two dimensional solution. You accidentally undock a window and have it hanging on your mouse while you try to put it back where it was. It would be better to use conventional splitters and tab controls to put it all together into a logical layout.
20	20
21	21		- Associated windows should be converted to Frames and then placed on a single form or tab page on the main form
22	22		- 1\. There should be a Welcome Page having new project wizards, a list of recent projects, help and resources
23	23		- 2\. A Development tab containing sub tabs for code and for form design
24	24
25	25		:* a. Code tab including Code Explorer, Source Editor and Project Manager
26	26
27	27		:* b. Form design tab including Object Inspector, Form designer and Component Palette
28	28
29	29		- 3 Debug tab containing the Debug windows as Frames.
30	30
31	31		- 4 since an integrated IDE has less screen real estate, swapping in and out windows need to be easier.
32	32
33	33		:* a. Probably a view concept is needed (different layout in debug then in normal (debug)). Maybe differentiate dependning on the F12 state (designer visible) too.
34	34
35	35		:* b. Big missing feature is the ability to let tabs page in from the side (a tab system to the left and right from the screen, ideal for process manager). When such tab loses focus, it pops back.
36	36
37	37		## Auto-generated database form
38	38
39	39		If you have set up a TSQLQuery, it would be nice to be able to let the IDE autogenerate a from with appropriate controls for all fields. --BigChimp 16:39, 8 August 2014 (CEST)
40	40
41	41		## Easier Dragging & Dropping
42	42
43	43		### Ideas that have been implemented
44	44
45	45		Done in 0.9.29: Options / Form editor / Ask name on create pool: after you add a component at Form, what is your next action? Editing Name/Caption in OI. Would be nice having OI focused and a key field like Name/Caption/Text selected. It would be very intuitive just having to type after dropping the component.
46	46
47	47		## Common
48	48
49	49		- enable menu access through access keys like under windows (i hate mouse sessions :o)
50	50
51	51		example: \<alt\>-\<f\> for file menu. Question: what operating system/widget set are you talking about?
52	52
53	53		### Ideas that have been implemented
54	54
55	55		- (Done in 1.1) Open files in the same folder as the current tab editor, like SCite does, it's a bit annoying to navigate from folder to folder every time you need open a file related to the one we are editing at the moment.
56	56
57	57		## Source Editor
58	58
59	59		- Multiple splitting (and close the split) the editor to horizontal and vertical views like with VIM, so I can do split for example Vertically, and inside do a split for Horizontal editor. And we can close each split by right click on the movable splitter and select it from a menu item.
60	60
61	61		- VIM keyboard support - require implementation of a command line like that can accept keyboards like with the VIM text editor.
62	62
63	63
64	64		A good example is Qt Creator: you press Alt+V+V and get into FakeVim mode, where most vim commands work
65	65
66	66		Question: what do you mean by keyboard? Another keyboard layout? Different shortcuts keys? Shortcut keys can already be defined via the Tools menu
67	67
68	68		- Multi linguistic spell checkers for strings and comments, using aspell, hspell, ispell etc... (aspell and hspell already have binding for FPC)
69	69
70	70		### Ideas that have been implemented
71	71
72	72		- (Done in 0.9.27) When focusing/selecting one BEGIN the respective END should be in RED to show where it really ends.
73	73
74	74		- (Done in 0.9.29) Movable tabs, so we can place tabs as we wish instead of keeping them where they where opened.
75	75
76	76		- (Done in 0.9.27) Ability to have a way to fold code arbitrary by using comments with special chars such as
77	77
78		-	~~`some code {% /* } <-- start folding `\~~
79		-	~~` more code`\~~
80		-	~~` ...`\~~
81		-	~~` ...`\~~
82		-	~~`and more code {% */ } <-- stop folding `~~
	78	+	```text
	79	+	some code {% /* } <-- start folding
	80	+	more code
	81	+	...
	82	+	...
	83	+	and more code {% */ } <-- stop folding
	84	+	```
83	85
84	86		- Done: if you click on an error message, the cursor jumps to the code line in question and highlights it.Color code on errors with special underline or some type of color that the user can select/change that will help to locate where the problem is (not instead of the error message that exists today).
85	87
86	88		- Done: see below Ability to keep the string mark (that added to 0.9.27) of a word/selected string as permanent with a toggle of a menu item/key/toolbar or something
87	89
88	90
89	91		QUESTION: Does that refer to the "highlight all occurrences" of "word under caret"/"current selection"?
90	92
91	93		That is possible (try alt-M)
92	94
93	95		- (Done: Lazarus 1.0+: context-sensitive help is included with at least the windows installer. See [[Installing Help in the IDE]] Inline help for a command/reserve word that the mouse cursor/keyboard caret are under that word (not instead of the tooltip that exists today when the mouse is hover the command/variable).
94	96
95	97		- (Done) When pressing on CTRL on a file/variable/type etc.. that we are trying to load, it will place a tooltip telling what is going to be opened (the file + the line number) (The information is shown when hovering over the variable)
96	98
97	99		- Done in 0.9.29 Ability to save and load color scheme for syntax highlight.
98	100
99	101		- Done (present in at least 1.2): see Edit/Find in Files which has a replace option Within the "Edit" menu, add an option called "Replace in files...", which allow find and replace text in all the units of the application, doing it at once.
100	102
101	103		### Improvement of the menu and toolbars
102	104
103	105		- to allow end user customization
104	106		- to obtain more styled menu (similar as Shagrouni xp-menu style)
105	107
106	108		## Integrated and Working Debugger
107	109
108	110		Debugging from inside the IDE can be a frustrating process. I believe this is a combination of GDB being more C/C++ centric, or because it is a more generalized standalone debugger. Either way, I think the ultimate solution is to write a custom debugger for use with FPC and Lazarus IDE. This way it will be possible for the debugger to support ALL Object Pascal and Lazarus IDE requirements, or maybe even be compiled into the Lazarus IDE itself. GDB does support Object Pascal, but not nearly at the level it does with C/C++.
109	111
110	112		An IDE without sufficient debugging support is a hard sell to would-be contributors or Delphi converts. This might also have contributed to some of the negative comments received in the Delphi non-technical newsgroup. Make no mistake, I love the many unique IDE features Lazarus has to offer - it beats Delphi IDE by far.
111	113
112	114		Apart from the standard Lazarus debugging solution using gdb there are multiplle custom written debuggers, partly or completely implemented in Object Pascal:
113	115
114	116		- [[FpGdbmiDebugger]]: uses gdb but also adds Pascal code. In development, experimental; included with Lazarus
115	117		- [[FpDebug]]: Located at components\lazdebuggers\lazdebuggerfp\LazDebuggerFp.lkp Currently support Linux and Windows
116	118		- [Duby](http://sourceforge.net/projects/duby/): A research project on SourceForge.net.
117	119		- [fpdebug (fork of duby)](https://github.com/graemeg/fpdebug): It's a fork of Duby with some further development work. I didn't know about the name conflict with the Lazarus one though. The joys of the FP* prefix. :)
118	120
119	121		Please try out these projects and contribute if you can.
120	122
121	123		## Object Inspector
122	124
123	125		### Search field
124	126
125	127		add a "search" text box at the top or bottom (preferred, maybe user settable) of Object Inspector to be able to search for a name or value (maybe with right click menu checkable options on whether Name or Value or both are searched) in the properties/events list
126	128
127	129		Question: What about sub properties?
128	130
129	131		### Recent page
130	132
131	133		add a "Recent" tab to Object Inspector apart from the "Favorites" one, would be more useful than the Favorites one since it's automatic (would keep all properties/events that have been edited \[fields that have either been changed or ENTER was pressed to CONFIRM/REset their current value - focus lost events shouldn't be considered editing if value of property/event field didn't change\])
132	134
133	135		Question: How are items removed from the list?
134	136
135	137		### Not registered component classes
136	138
137	139		Add a field in the object inspector to allow specifying the real class that will be instantiated, with that will allow to uses derived classes without remake/link the IDE, of course the new fields for the real class will not be available to edit in designer. An example: We place a TEdit in a form, but we want to use a derived class we made that add a new field/property/method to TEdit and we will use that new field/property/method programming but in design time it's enough to work with TEdit, actually there is an option to change the class but only to another one that's already linked on the IDE.
138	140
139	141		> Note: The class must be registered. This is needed for streaming and RTTI. If you don't want to register the real class, then register a fake class. It would be possible to create an artificial derived class from a registered component class on the fly. This has nothing to do with the OI. A dialog to manage all artificial classes must be implemented and a menu item must be added somewhere.
140	142
141	143		## Refactoring
142	144
143	145		### Global Variable/Method renaming
144	146
145	147		Proper renaming (as in if I rename a field in an object it can change everything that uses it but NOT other stuff that happens to have the same name) -Plugwash
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147	149
148	150		Already implemented: See Source Editor -\> popup menu -\> refactoring -\> rename identifier
149	151
150	152		### Parameter Renaming in Methods
151	153
152	154		adding a parameter to a method (and updating everything that uses it) -Plugwash
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154	156
155	157		How should that work? What should the IDE/codetools put as parameter at the places?
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157	159
158	160		You specify that when you ask for the parameter to be added. Plugwash 05:09, 30 September 2006 (CEST)
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160	162		For example, you add a parameter "b: boolean". The method is used a 100 times.
161	163
162	164		- Possibility 1: You add a default parameter too. No change to the using methods is needed.
163	165		- Possibility 2: You press compile and the compiler will jump to every occurence and you can decide, what to do.
164	166		- Possibility 3: A new dialog is added to the IDE, where you can specify to insert a ",false" at every occurence.
165	167		- Possibility 4: ?
166	168
167	169		Do you have 3 in mind or 4?
168	170
169	171		### Parameter reordering
170	172
171	173		like Delphi. A dialog to add, remove, reorder parameters of a function, method, property.
172	174
173	175		### Improvement of the IDE like GExperts does for Delphi
174	176
175	177		- Done: see Project/Publish project Backup tool...
176	178		- Tab : provision to set Tab spacing
177	179
178	180
179	181		Question: please indicate what you specifically miss in Tools/Editor/General/Tab and Indent
180	182
181	183		- Rename Components (where it is possible too, to fill some properties in this moment. f.e. Button: Caption, Width, Height, Action)
182	184
183	185		## I have a dream of components : Jedi
184	186
185	187		Sure I switch immediately from Delphi to Lazarus.
186	188
187	189		- The Jedi components are a mix of OS dependant, Borland dependant and architecture specific code. I doubt these will ever work on anything but windows/x86. (and maybe win64 with a bit shoehorning). Example: To use a string routine in the strings unit of JCL, you have to fix like 12 units, some of which poke around in the Borland specific debug code. And then you haven't even reached the units of the JVCL, besides this there is a [[licensing]] problem. Marcov 18:27, 4 October 2008 (CEST)
188	190		- A lot of Jedi code has been implemented in FPC already. Question: do you need more? What components exactly? --BigChimp 15:16, 28 March 2014 (CET)
189	191
190	192		## Code completion
191	193
192	194		### Create/Free objects
193	195
194	196		Declare an object myObj:TMyClass into a TForm class an type some Ctrl-Shift-Key, then the IDE adds a line myObj:=TMyClass.Create in FormCreate and myObj.Free in FormDestroy. -Rednaxel
195	197
196	198		### Add list properties
197	199
198	200		Declaring an indexed property like 'property Items\[i: integer\]: TAType' and using this feature (Ctrl-Shift-Key, Menu), should popup a dialog to setup some parameters and then it should add a private variable fItems: TFPList; (or 'array of' or TList or ^AType), create code in the constructor, destroy code in the destructor and access methods GetItems, SetItems.
199	201
200	202		## Visual Form Inheritance
201	203
202	204		VFI (Visual From Inheritance) works in Lazarus but there are some missing features:
203	205
204	206		- When ancestor and descendant are open in the IDE and a property of the ancestor is changed, then change the descendant too.
205	207
206	208		## Conditional Compiler Options
207	209
208	210		See [[Conditional Compiler Options]].
209	211
210	212		## Help
211	213
212	214		### A small tutorial for Object Oriented Programming
213	215
214	216		I wish to have in Lazarus as in Eclipse in the Help menu a Tutorial for Object Oriented Programming.
215	217
216	218		- This is a good idea, but I think a offline help browser is first required. Lucky for you, I already implemented such a beast, called [DocView](http://sourceforge.net/projects/fpgui/files/fpGUI/1.4/). :-) I also have a few old programming manuals around that could contribute to the contents. I know Borland released the OOP chapter what was included in the Turbo Pascal v5.5 & v6 manuals for everybody to use (freely downloadable). So maybe that will be the best place to start. A downloadable copy of the OOP Chapter can be found [here](http://geldenhuys.co.uk/articles/). I also have freely available INF e-books (viewable with DocView) that cover the introduction to Object Pascal and OOP programming (follow [this](http://geldenhuys.co.uk/~graemeg/inf_books/) link) --Ggeldenhuys 13:44, 29 November 2013 (GMT)
217	219		- Offline help has been included since Lazarus 1.0x with lhelp and the chm format. A help menu item that shows lhelp is included with Laz trunk. Maybe the .inf books could be converted to chm and included with the Lazarus installer --BigChimp 14:21, 30 November 2013 (CET)
218	220
219	221		## Better Macro support by making them easier to find
220	222
221	223		See the feature request [\#14558](http://bugs.freepascal.org/view.php?id=14558) in Mantis. In summary, add a button next to EditBox controls which support macro usage. Clicking the button will display a popup menu with available macros at that level and insert the selected macro into the EditBox at the cursor position.
222	224
223	225		## Copy and Paste Support for a lazy programmer (in properties-editor)
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225	227		Maybe it's by design (because of the same behaviour under win and mac)... but I think, it's a little bit of annoying. When I try to copy the chosen "name" of a component out of proterties-editor by selecting it and ctrl+c, I will not get the text of the name, but the object/component description itself (which is useless, I guess). There is not even a "copy" item in the context-menu. I use very long descriptive names for components (and variables) and it would be nice, to get these unhandy names somehow into the clipboard. KaLi 14:56, 30 June 2010 (CEST)
226	228
227	229
228	230		This seems to work in 0.9.31, both Ctrl+C and via context-menu [Bart](http://wiki.lazarus.freepascal.org/User:Bart)
229	231
230	232		## Code Library Window or Tab
231	233
232	234		It would be great to have a built in location to store all those useful pieces of code. Ones that you have created, or found useful.
233	235
234	236		My ideal feature list would be:
235	237
236	238		- Save and Load my personal code
237	239		- Attach Zip file ( useful for keeping a sample project, showing the code in use).
238	240		- Ability to Upload Code / zip to central online repository.
239	241		- Ability to synchronize or select repository code and download to my own code store.
240	242		- Code could be sectioned into well thought out categories, like Types of controls, Libraries, complete project examples, Tutorials, etc.
241	243		- A place to show the most recent code submitted by Category.
242	244
243	245		It would also be a good place to help people who need some assistance. I would have the following options:
244	246
245	247		- Option to Ask for help on a control or subject matter.
246	248		- Notification when a solution is uploaded to the repository.
247	249		- Maybe a points system rating the assistance given out of 10 ( 1 being not useful, 10 being just what I needed)
248	250
249	251
250	252		The "Code Librarian" third party code library tool is available made by Lazarus forum user taazz. Helping him with incorporating these features (if he wants to) could be the best way of getting this functionality: <http://forum.lazarus.freepascal.org/index.php/topic,22752.0.html> and <https://sourceforge.net/projects/codelibrarian/>
251	253
252	254		## Write and run unit tests from subpackage of project being tested
253	255
254	256		The main idea is to have ability to write and run Unit tests from a subpackage of main project. Please see [[Feature Ideas/UnitTests]]
255	257
256	258		# LCL
257	259
258	260		## Components
259	261
260	262		Components that are possible to make that will work across all platforms supported by Lazarus
261	263
262	264		- Do you mean customdrawn components? If so, that is already possible. I think the TStringGrid is a customdrawn component. Alternatively, look at [[fpGUI]] for a completely customdrawn GUI toolkit. --Ggeldenhuys 23:56, 30 September 2009 (CEST)
263	265
264	266		### Visual
265	267
266	268		- The existing TDBLookupComboBox, could be greatly enhanced by something like an ".IsFiltered property": If true, the control should reduce its list of visible (and hence selectable) values in the dropdown list by filtering the DataField by the current DBLookupComboBox while editing. This means, onChange (resulting in DBLookupComboBox.Text updated to someString) automatically reduces the list to SELECT lookup_field FROM lookup_table WHERE lookup_field LIKE %'+someString+'%. A feature like that would greatly enhance the usability of Lazarus made database applications!\
267	269		To illustrate this idea, compare other similar projects: [1](https://www.freelancer.com/projects/Delphi/Custom-Delphi-TDBLookupComboBox/) [2](https://www.devexpress.com/Support/Center/Question/Details/B196085/filtering-dataset-of-tcxdblookupcombobox) or [3](https://www.drupal.org/sandbox/jauzah/1748434), or this [screenshot](https://www.drupal.org/files/project-images/select2element_screen.jpg) .
268	270
269	271		- Already implemented [[Add Help to Your Application]]: Help system for apps created by Laz! It is a plugin system. That's why it supports cross-platform help system and using the OS's native help system.
270	272
271	273		- The current LCL TStringGrid is a nice improvement over Delphi's feeble control with the same name. Would be great if it could be improved even more!
272	274		- Support for data validation event handler, similar to Orpheus grid's OnUserValidation event. There are many events, for example OnEditingDone, and OnValidateEntry to do this. See [[Grids Reference Page]] and [[Event order]]
273	275		- Support for retrieving, displaying, editing and storing data that are stored in an existing memory structure or in a file rather than in grid itself, similar to the Orpheus grid's OnGetCellData and OnGetCellAttributes events. There is the TTIGrid, that can show TCollection, TList and TFPList of TPersistent. What else do you need? Additionally, you can bind a TBufDataset to a dbgrid...
274	276		- A TImage component wich support transparent winxp alpha 32 bit icon images
275	277		- Support for RightToLeft BidiMode. Fixed in 0.9.31 according to <http://bugs.freepascal.org/view.php?id=18918>. Bug report tracking all RTL/Bidi: <http://bugs.freepascal.org/view.php?id=19303> If there are still bugs, please report them to the bug tracker.
276	278		- TTrayIcon
277	279		- Add a TImageList property in TTrayIcon to change TrayIcon icon or animate it
278	280
279	281		### NonVisual
280	282
281	283		- Clipboard and TTimer that don't depend on LCL. If you use these in a library or console app, the compiler drags in a lot of unused and unneeded LCL code. If you have multiple DLL's, this code is duplicated in each. Current implementations appear to follow the Delphi design approach, where Clipboard and TTimer have dependencies on the VCL - this probably wasn't necessary.
282	284		- TfpTimer is a non-LCL timer already available in FPC in unit fptimer.pp. Online help is available [here](http://lazarus-ccr.sourceforge.net/docs/fcl/fptimer/index.html). --Ggeldenhuys 14:38, 2 September 2009 (CEST)
283	285		- This may be true on Windows, but it´s False for Linux. I recently implemented TTimer for qt interface and the implementation calls Qt API. I think the same applies to Clipboard, since the clipboard depends on the widgetset used too (gtk or qt for example), not only on the operating system. --Sekelsenmat 20:40, 5 Mar 2006 (CET)
284	286		- The LCL is a visual component library. None visual components are provided by the FCL.
285	287		- Lazarus will only provide components based on the LCL.
286	288
287	289		## PDA Support
288	290
289	291		Something that currently does not exist is a complete multiplatform solution for PDAs. If we can implement this, Lazarus will become the first multiplatform RAD for PDAs ever created. Some devices work with Java, some work with c++ and Qtopia, some work with their particular APIs, there is no single solution currently that can embrace a large portion of PDAs. Application have to be redone for every PDA or simply just run on one of them (what most people do).
290	292
291	293		The LCL implements many things. It is not necessary to implement them all to have a reasonably working Lazarus PDA widgetset. The most important things to be implementeded for PDAs are:
292	294
293	295		- TApplication
294	296		- TForm
295	297		- TScreen
296	298		- TCanvas and painting
297	299		- Most Events (onClick and OnPaint at least)
298	300		- Basic widgets like: TButton, TLabel, TEdit, TMemo.
299	301		- Only minimum necessary LCLIntf functions to make TCanvas work. (GetDC, ReleaseDC, BeginPaint, EndPaint and some painting functions)
300	302
301	303		Others can be easily implemented by people who need them after those are ready.
302	304
303	305		Here is a list of some PDAs and the status of their support on Free Pascal / Lazarus:
304	306
305	307		- Windows CE - The compiler already works really well cross compiling for Windows CE. The [[Windows CE Interface]] is under implementation.
306	308		- Symbian OS - Possible for their ARM devices. Requires first adding a new Runtime Library for this OS to the Compiler. This OS has it's own API. There are open source projects for python and c to work on Symbian OS, so Free Pascal should work as well when a RTL is written.
307	309		- Qtopia - For Zaurus and other linux-based PDAs. This is much easier now that basic Qt4 widgetset has being implemented, because Qtopia is very similar to Qt4. Some magick on the bindings is expected to make the same widgetset code to run for both Qtopia and Qt4.
308	310		- Java - Some handheld devices, specially phones, only support java bytecode. May seam a little odd, but there is a Pascal Compiler capable of compiling the source into a jar and then into bytecode. It's name is Midlet Pascal <http://www.midletpascal.com/> It may be possible to develop a similar technology that adds a java bytecode target for Free Pascal. Some people already start porting midletpascal to delphi <http://forum.boolean.name/attachment.php?attachmentid=7975&d=1255392966>, follow instructions on <http://www.pascalgamedevelopment.com/forum/index.php?topic=5466.0> to access it.
309	311		- Palm OS - PalmOS 5 Garnet support requires that first the 68k compiler is working (runs on ARM processor with a kind of emulation) and then a RTL for palmos needs to be written. Only Free Pascal 1.0 supports 68k, this wasn't updated and the new compiler 2.0 doesn't support it yet (work in progress by [[fpc:User:Chain-Q]]), so will be a problem.
310	312
311	313		PalmOS 6 Cobalt is fully arm, so it only requires a rtl, but it has zero devices working on it currently and won't be on the market until 2007 at least.
312	314
313	315		Other compilers that support this target: [Pascal & Palm Compiler](http://www.ppcompiler.org) and [HsPascal](http://hspascal.fihl.net/). Unfortunately those compilers are not open source, so we can't use their code, we need to implement PalmOS RTL from zero.
314	316
315	317		## More Interfaces
316	318
317	319		- Cocoa - Requires that first OpenSTEP bindings are created for Free Pascal. Cocoa interface support has been started; see [[Cocoa Interface]]
318	320		- BeAPI - interface for Haiku, ZetaOS and BeOS. There is no powerful RAD on this OS.
319	321		- Bindings to the BeAPI has been started - though not part of the Lazarus project. Have a look at SourceForge [befpc](http://befpc.sourceforge.net/) project.
320	322		- [SDL](http://www.libsdl.org) - something like what was done in [Pixel Image Editor](http://www.kanzelsberger.com/pixel/).
321	323		- MacApp 2.0 - For 68k-based Mac computers. MacApp was Apple Computer's primary object oriented application framework for the Mac OS for much of the 1990s. First released in 1985, it is arguably the first such system to be widely used, notably on a microcomputer platform. Microsoft's MFC and Borland's OWL were both based directly on MacApp concepts. This framework was completely written on Object Pascal, so it should integrate really nicely with Free Pascal and Lazarus. When Apple moved to PowerPC it also dropped Object Pascal support, but that's another story. A emulator for 68k-Mac can be easely set up with [BasiliskII](http://basilisk.cebix.net/). There is also a project called MacApp2PPC that upgraded MacApp pascal code to run on Power PCs.
322	324		- OS/2 native - Free Pascal works well with OS/2, so this should be quite possible.
323	325		- Solaris - OpenSolaris versions exist and it's quite similar to Linux so why not ? For information on the Solaris port of Lazarus, see: [[Lazarus on Solaris]]
324	326		- Web Interface - Application compiles to an embedded HTTP Server who serves forms in ajax pages (or compiles it to an Apache Module), like Intraweb in Delphi. Discussion in <http://www.lazarus.freepascal.org/index.php?name=PNphpBB2&file=viewtopic&t=2489>
325	327		- Already implemented: [fpGUI](http://fpgui.sourceforge.net/) - A widget set written in Free Pascal without any large library requirements. fpGUI talks directly to the underlying graphics library and is very easy to port to new platforms. Currently it supports Linux, ARM-Linux, FreeBSD, Windows and WinCE. - Under development here: [[fpGUI Interface]]
326	328
327	329		### improved EventQueue
328	330
329	331		- [[Lazarus improved Event Queue]]
330	332
331	333		### Lua
332	334
333	335		- Support for Lua interfacing. (Binary modules?)
334	336		- What is Lua interfacing? Is it a graphical widgetset? What is the difference between what you want and is supplied by the lua units of fpc: <http://svn.freepascal.org/svn/fpc/trunk/packages/lua/>
335	337		- Perhaps the poster wanted to use the Lua scripting language to access the LCL widgetset. Had a quick look at the FPC lua package mentioned above: no readme, no test, no demo, so not easy to see what that package does/can do. Perhaps it can be used as-is to do what the poster wants; in that case, some additional samples/documentation may be handy. BigChimp, September 2012
336	338
337	339		# Visual Improvements
338	340
339	341		## An idea for a splash screen
340	342
341	343		![](/wiki-images/e/ea/Splash_logo2_.png%E2%80%8E)
342	344
343	345		The font for "write once..." is DejaVue Serif Condensed, for "Lazarus" is Phantom, and for "object pascal" is Tahoma.
344	346
345	347		If you want to change the splash logo on Windows, in your main Lazarus installation folder find "images" folder and there find "splash_logo.bat". Then edit and run it or replace "splash_logo.png" and run "splash_logo.bat".
346	348
347	349		### critique
348	350
349	351		- as if people's desktops are not already cluttered to the max... not desirable
350	352
351	353		# FPC
352	354
353	355		## Per-type Byte Alignment
354	356
355	357		A means to align variables and records in a unit is already possible with compiler directives, but is somewhat messy and might cause conflicts in some situations. What I propose is an addition to the Free Pascal syntax that forces all variables of a defined type to be aligned to a particular boundary. e.g.
356	358
357	359		``` pascal
358	360		type
359	361		AlignedDouble = Double align 16;
360	362
361	363		type
362	364		TVector4f = packed record
363	365		X, Y, Z, W: Single;
364	366		end align 16;
365	367
366	368		type
367	369		TVector4fArray = array of TVector4f align 32;
368	370		{ tighter restrictions than TVector4f, so it's okay. Note that this should probably align Var[0] to a 32-byte boundary, not necessarily Var as a whole }
369	371		```
370	372
371	373		Such aligned types are useful and even necessary for when working with SSE and AVX, where significant speed gains can be achieved with aligned data (and some operations require it).
372	374
373	375		Apparently Delphi supports something like this already, but it isn't well-documented.
374	376
375	377		### Nuances
376	378
377	379		- The exact syntax.
378	380		- Cross-platform support. Do all platforms support memory alignment?
379	381		- Exact error messages or behaviour if you specify a non-power of 2 alignment.
380	382		- What happens if you try to typecast an unaligned variable to an aligned type? (Aligned to unaligned should be fine)
381	383		- What happens if you try to typecast a pointer to an unaligned type to a pointer to an aligned type?
382	384		- What happens if you, say, declare a type aligned to 16 bytes, and then declare another type that is equal to it but is only aligned to 8 bytes?
383	385		- What happens if you, say, declare a type aligned to 16 bytes, then use it as a field in a record type, aligned or otherwise?
384	386
385	387		CuriousKit ([[User talk:CuriousKit\|talk]]) 18:28, 5 December 2017 (CET)
386	388
387	389		## "vectorcall;" modifier for Win32 and Win64
388	390
389	391		This function modifier is the only unique modifier for Win64 (although it can be used in Win32 too), introduced by Microsoft at the behest of game developers who wish to reduce the overhead of passing vectors and the like into subroutines. The basic details are the same as the regular Win64 calling convention, but attempt to vectorise certain record types and pass them in their entirety through a single XMM register (something which is already possible in Linux64 sometimes). Details can be found here: <https://msdn.microsoft.com/en-us/library/dn375768.aspx>
390	392
391	393		This may require the byte alignment feature described above.
392	394
393	395
394	396		vectorcall is implemented in (the upcoming) fpc 3.2 for the win64 platform. Bart
395	397
396	398		### Nuances
397	399
398	400		- What happens if it is used on a platform other than Win32 or Win64? Does a compiler error occur or is it ignored with a warning?
399	401
400	402		CuriousKit ([[User talk:CuriousKit\|talk]]) 23:04, 5 December 2017 (CET)
401	403
402	404		- - It is ignored with a warning. Bart ([[User talk:Bart\|talk]]) 17:43, 20 December 2022 (CET)
403	405
404	406		- As an example of prior art I think Vector Pascal[1](https://sourceforge.net/projects/vectorpascalcom/) is noteworthy. MarkMLl ([[User talk:MarkMLl\|talk]]) 09:12, 6 December 2017 (CET)
405	407
406	408		## "default"-value in a proc or function call
407	409
408	410		- There is a limitation in the freepascal-Syntax where you can not depend on the default-parameter lefthand from an explicit parameter. I suggest a possibility where you can say "default" in a function-call, and set other parameters at the same time.
409	411
410	412		``` pascal
411	413		program DefaultParameter;
412	414
413	415		{$mode objfpc}{$H+}
414	416
415	417		type
416	418		Pilots = (Charles, Amelia, Belly, Louis);
417	419
418	420		procedure Fly(Pilot: Pilots = Belly; Copilot: Pilots = Charles);
419	421		begin
420	422		if (Pilot=Copilot) then
421	423		halt(1);
422	424		end;
423	425
424	426		begin
425	427		Fly; // we fly with Belly+Charles
426	428		Fly(); // we fly with Belly+Charles
427	429		Fly(Amelia); // we fly with Amelia+Charles
428	430		Fly(Louis, Belly);
429	431
430	432		// The following "default" is my Feature Idea
431	433		// │
432	434		// v
433	435		Fly(default, Amelia); // we fly with Belly+Amelia
434	436		end.
435	437		```
436	438
437	439		### Critique
438	440
439	441		- If such a feature should exist, wouldn't it be more straightforward to simply not specify anything before the comma? (i.e. "Fly(, Amelia);") CuriousKit ([[User talk:CuriousKit\|talk]]) 14:50, 7 December 2017 (CET)
440	442
441	443		## "pure;" function directive
442	444
443	445		I propose a new directive keyword that can be specified for functions, named pure. Its intention is to act as a hint to the compiler that the function is fully self-contained, has no side-effects (although the compiler will actually check if this is the case) and is guaranteed to return the same output for a given input. An example would be the Int function, which returns the input value with the fractional part stripped off, and nothing else.
444	446
445	447		So what would be the advantage of a function being 'pure'? With a pure function, if the input values are constants, then the output(s) will also be constants, hence they can be pre-calculated during compilation and the function call completely replaced with an assignment, offering a massive speed boost and providing a sort of general-purpose means of doing what some internal compiler routines do in regards to replacing calls with static values.
446	448
447	449		There are potentially two ways that the compiler can determine if a function is pure:
448	450
449	451		- Perform deep analysis of the pre-compiled assembly language, almost like an emulator (platform-dependent, but will allow pure assembler routines to be considered for function purity, which may be beneficial for operations such as ROL, ROR, BSF and BSR).
450	452		- Run the subroutine's source code through PascalScript (largely platform-independent), and if unresolved reference errors occur, then the function can be considered impure.
451	453
452	454		In this case, the pure keyword gives a hint to the compiler as to which procedures to check for purity, so it doesn't waste a potentially long time on routines that the programmer already knows are impure.
453	455
454	456		If a function is marked as pure but it turns out not to be, the compiler throws a warning much like what happens if it's marked as inline, but something makes it an invalid candidate. The following paradigms would make a function a non-eligible candidate:
455	457
456	458		- Reading from or writing to external memory (including static and global variables)
457	459		- Reading from or writing to I/O
458	460		- Contains var parameters (since, by definition, they cannot be a constant)
459	461		- Dereferencing a pointer (which also means object methods cannot be made pure, including constructor and destructor since, by definition, they allocate and deallocate memory related to object instantiation. I don't think class methods can be pure either) - the only exception to this are out parameters, since their type and size are tightly controlled and the dereferencing is effectively hidden from the programmer anyway.
460	462		- Allocating or deallocating memory
461	463		- Obtaining the address of something (using the @ operator)
462	464		- Calling another function (unless that function is also pure, in which case, pre-computing an output becomes a recursive operation. Note that actual recursion, where a function calls itself, is allowed and may be required in places... for example, with an implementation of a factorial function)
463	465		- There are code paths where uninitialized values can be read (this includes reading an out parameter prior to writing to it).
464	466
465	467		There are probably other things that prevent a function from being pure.
466	468
467	469		pure will generally only be used on functions; procedure is nevertheless valid because the output may be an out parameter, so long as the procedure's body follows all of the rules of a pure function.
468	470
469	471		### Nuances
470	472
471	473		- What happens if the pre-computation of an output value would cause an exception to be raised (e.g. division by zero)?
472	474		- What happens if the pre-computation would cause an infinite loop? How well can this be detected via finite state analysis rather than a timeout? (It's likely very difficult to do it purely via finite states - see [Turing's Halting Problem](https://en.wikipedia.org/wiki/Halting_problem)).
473	475		- What happens if a constant is declared to equal a pure function (e.g. "const QuarterPi = atan(1);" if atan is declared and proven pure). On the surface this seems perfectly valid, but what happens if optimizations are turned off?
474	476
475	477		CuriousKit ([[User talk:CuriousKit\|talk]]) 01:20, 17 June 2018 (CEST)
476	478
477	479		## Support for Traits
478	480
479	481		As a user who never got warm with the concept of interfaces, I'd like to suggest support for traits [2](https://en.wikipedia.org/wiki/Trait_(computer_programming)).
480	482
481	483		## Support for Promises
482	484
483	485		I know there are TThread.ExecuteInThread, Synchronize, Queue, etc. But JavaScript's promises [3](https://en.wikipedia.org/wiki/Futures_and_promises) are so intuitively to use that I'd love to see support in FPC. Could be an enormously handy feature when dealing with tasks for which, on the one hand, TThread would be overdimensioned, but on the other hand, doing the task in the main thread would on the other hand cause lags. I'm especially thinking about web requests, loading data from a file (which could be on a network drive), etc.
484	486
485	487		# Other
486	488
487	489		## Fixes branch releases
488	490
489	491		Already done: Currently we only have snapshots of the fixes branch, and it would be nice to also have them as releases. To have releases, those builds would have to be tested by someone, so I volunteer for that. What is needed is a testing checklist, and the start of it can be found on my page, User:Arny. Any further ideas are welcome!
490	492
491	493		- This is already done and maintained for v0.9.28 onwards of Lazarus. Downloads of fixes releases are available on SourceForge.
492	494
493	495		## See Also
494	496
495	497		- [[Bounties]] - A way to make sure your feature idea is implemented.
496	498		- [[How do I create a bug report]] general information on submitting bugs, what should be covered in a bug report, and using the bug tracker.
497	499		- [[Tips on writing bug reports]] detailed information on what should be covered in a bug report.
498	500		- [[Database bug reporting]] Specific info and sample programs for database bugs
499	501		- [[Moderating the bug tracker]]
500	502
501	503		---
502	504		From the Free Pascal wiki, page "Feature Ideas", as it stood on 2022-12-20 after a change by Bart, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).
503	505		Category: Lazarus
504	506		Category: Proposals

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