Add comments to fork() logic for readibility
[notion/jeffpc.git] / ioncore / ioncore_bindings.lua
blob01588ebaed474057aff36fb5be578232a71d2746
1 --
2 -- ion/share/ioncore-bindings.lua
3 --
4 -- Copyright (c) Tuomo Valkonen 2004-2009.
5 --
6 -- See the included file LICENSE for details.
7 --
9 local ioncore=_G.ioncore
11 local warn=ioncore.warn
13 local compiled2str=setmetatable({}, {__mode="k"})
15 --DOC
16 -- Compile string \var{cmd} into a bindable function. Within \var{cmd}, the
17 -- variable ''\var{_}'' (underscore) can be used to refer to the object
18 -- that was selecting for the bound action and chosen to handle it.
19 -- The variable ''\var{_sub}'' refers to a ''currently active'' sub-object
20 -- of \var{_}, or a sub-object where the action loading to the binding
21 -- being called actually occured.
22 --
23 -- The string \var{guard} maybe set to pose limits on \code{_sub}. Currently
24 -- supported guards are \code{_sub:non-nil} and \code{_sub:WFoobar}, where
25 -- \type{WFoobar} is a class.
26 function ioncore.compile_cmd(cmd, guard)
27 local guardcode=""
28 local gfn=nil
30 if guard then
31 local st, en, condition=string.find(guard, "^_sub:([%w-_]+)$")
32 local sub='_sub'
33 if not condition then
34 st, en, condition=string.find(guard, "^_chld:([%w-_]+)$")
35 if condition then
36 sub='_chld'
37 end
38 end
40 if not condition then
41 ioncore.warn_traced(TR("Invalid guard %s.", guard))
42 elseif condition=="non-nil" then
43 guardcode='if not '..sub..' then return end; '
44 else
45 guardcode='if not obj_is('..sub..', "'..condition..'") then return end; '
46 end
48 local gfncode="return function(_, _sub, _chld) "..guardcode.." return true end"
49 local gerr
50 gfn, gerr=loadstring(gfncode, guardcode)
51 if not gfn then
52 ioncore.warn_traced(TR("Error compiling guard: %s", gerr))
53 end
54 gfn=gfn()
55 end
57 local function guarded(gfn, fn)
58 if not gfn then
59 return fn
60 else
61 return function(_, _sub, _chld)
62 if gfn(_, _sub, _chld) then
63 fn(_, _sub, _chld)
64 end
65 end
66 end
67 end
69 if type(cmd)=="string" then
70 local fncode=("return function(_, _sub, _chld) local d = "
71 ..cmd.." end")
72 local fn, err=loadstring(fncode, cmd)
73 if not fn then
74 ioncore.warn_traced(TR("Error in command string: ")..err)
75 return
76 end
77 compiled2str[fn]=cmd
78 return guarded(gfn, fn())
79 elseif type(cmd)=="function" then
80 return guarded(gfn, cmd)
81 end
83 ioncore.warn_traced(TR("Invalid command"))
84 end
87 local function putcmd(cmd, guard, tab)
88 local func
89 if cmd then
90 func=ioncore.compile_cmd(cmd, guard)
91 if type(func)~="function" then
92 return
93 end
94 end
96 tab.func=func
97 tab.cmdstr=cmd
98 tab.guard=guard
100 return tab
103 --DOC
104 -- Used to enter documentation among bindings so that other programs
105 -- can read it. Does nothing.
106 function ioncore.bdoc(text)
107 return {action = "doc", text = text}
110 --DOC
111 -- Returns a function that creates a submap binding description table.
112 -- When the key press action \var{keyspec} occurs, Ioncore will wait for
113 -- a further key presse and act according to the submap.
114 -- For details, see Section \ref{sec:bindings}.
115 function ioncore.submap(keyspec, list)
116 if not list then
117 return function(lst)
118 return submap(keyspec, lst)
121 return {action = "kpress", kcb = keyspec, submap = list}
124 --DOC
125 -- Creates a binding description table for the action of pressing a key given
126 -- by \var{keyspec} (with possible modifiers) to the function \var{cmd}.
127 -- The \var{guard} controls when the binding can be called.
128 -- For more informationp see Section \ref{sec:bindings}.
129 function ioncore.kpress(keyspec, cmd, guard)
130 return putcmd(cmd, guard, {action = "kpress", kcb = keyspec})
133 --DOC
134 -- This is similar to \fnref{ioncore.kpress} but after calling \var{cmd},
135 -- Ioncore waits for all modifiers to be released before processing
136 -- any further actions.
137 -- For more information on bindings, see Section \ref{sec:bindings}.
138 function ioncore.kpress_wait(keyspec, cmd, guard)
139 return putcmd(cmd, guard, {action = "kpress_wait", kcb = keyspec})
142 --DOC
143 -- Submap enter event for bindings.
144 function ioncore.submap_enter(cmd, guard)
145 return putcmd(cmd, guard, {action = "submap_enter"})
148 --DOC
149 -- Submap modifier release event for bindings.
150 function ioncore.submap_wait(cmd, guard)
151 return putcmd(cmd, guard, {action = "submap_wait"})
154 -- DOC
155 -- Submap leave event for bindings.
156 --function ioncore.submap_leave(cmd, guard)
157 -- return putcmd(cmd, guard, {action = "submap_leave"})
158 --end
160 local function mact(act_, kcb_, cmd, guard)
161 local st, en, kcb2_, area_=string.find(kcb_, "([^@]*)@(.*)")
162 return putcmd(cmd, guard, {
163 action = act_,
164 kcb = (kcb2_ or kcb_),
165 area = area_,
169 --DOC
170 -- Creates a binding description table for the action of clicking a mouse
171 -- button while possible modifier keys are pressed,
172 -- both given by \var{buttonspec}, to the function \var{cmd}.
173 -- For more information, see Section \ref{sec:bindings}.
174 function ioncore.mclick(buttonspec, cmd, guard)
175 return mact("mclick", buttonspec, cmd, guard)
178 --DOC
179 -- Similar to \fnref{ioncore.mclick} but for double-click.
180 -- Also see Section \ref{sec:bindings}.
181 function ioncore.mdblclick(buttonspec, cmd, guard)
182 return mact("mdblclick", buttonspec, cmd, guard)
185 --DOC
186 -- Similar to \fnref{ioncore.mclick} but for just pressing the mouse button.
187 -- Also see Section \ref{sec:bindings}.
188 function ioncore.mpress(buttonspec, cmd, guard)
189 return mact("mpress", buttonspec, cmd, guard)
192 --DOC
193 -- Creates a binding description table for the action of moving the mouse
194 -- (or other pointing device) while the button given by \var{buttonspec}
195 -- is held pressed and the modifiers given by \var{buttonspec} were pressed
196 -- when the button was initially pressed.
197 -- Also see section \ref{sec:bindings}.
198 function ioncore.mdrag(buttonspec, cmd, guard)
199 return mact("mdrag", buttonspec, cmd, guard)
202 --DOC
203 -- Define bindings for context \var{context}. Here \var{binding} is
204 -- a table composed of entries created with \fnref{ioncore.kpress},
205 -- etc.; see Section \ref{sec:bindings} for details.
206 function ioncore.defbindings(context, bindings)
207 local function filterdoc(b)
208 local t={}
209 for k, v in ipairs(b) do
210 local v2=v
211 if v2.submap then
212 v2=table.copy(v)
213 v2.submap=filterdoc(v2.submap)
215 if v2.action~="doc" then
216 table.insert(t, v2)
219 return t
221 return ioncore.do_defbindings(context, filterdoc(bindings))
224 local function bindings_get_cmds(map)
225 for k, v in pairs(map) do
226 if v.func then
227 v.cmd=compiled2str[v.func]
229 if v.submap then
230 bindings_get_cmds(v.submap)
235 --DOC
236 -- Get a table of all bindings.
237 function ioncore.getbindings(maybe_context)
238 local bindings=ioncore.do_getbindings()
239 if maybe_context then
240 bindings_get_cmds(bindings[maybe_context])
241 return bindings[maybe_context]
242 else
243 for k, v in pairs(bindings) do
244 bindings_get_cmds(v)
246 return bindings