NETIO Lua Manual - Revision history

Bbakala: Redirected page to Welcome to NETIO resources & projects & documentation overview

2019-07-11T17:01:04Z

Redirected page to Welcome to NETIO resources & projects & documentation overview

Bbakala: /* Periodical scipts */

2019-07-11T16:33:31Z

‎Periodical scipts

Bbakala: /* Periodical scipts */

2019-07-11T16:33:09Z

‎Periodical scipts

Bbakala at 16:28, 11 July 2019

2019-07-11T16:28:00Z

Bbakala: /* Periodical scipts */

2019-07-11T16:27:31Z

‎Periodical scipts

Bbakala: /* LUA script starting */

2019-07-11T16:21:52Z

‎LUA script starting

Bbakala: /* Script triggering */

2019-07-11T16:21:29Z

‎Script triggering

Phrych at 15:50, 11 July 2019

2019-07-11T15:50:34Z

Phrych at 15:49, 11 July 2019

2019-07-11T15:49:13Z

Jturon: /* Data types and variables */

2017-05-06T08:34:56Z

‎Data types and variables

← Older revision		Revision as of 17:01, 11 July 2019
Line 1:		Line 1:
−	~~== Script starting ==~~	+	#REDIRECT [[Welcome to NETIO resources & projects & documentation overview]]
−	LUA Scripts in NETIO are event driven. That means if some [[NETIO Lua Reference\| event]] is triggered the script run exactly once. One of "triggers" is for example [[System started up\|System started up]]. You can find list of all events called "triggers" in [[~~NETIO Lua Reference\|NETIO Lua Reference]].~~
−
−	~~== Periodical scipts ==~~
−	In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds) usng standard triggers. For such scripts the trigger [[System started up\|System started up]] and the function [[delay()\|delay()]] must be used. This function calls itself and allows to ~~run some procedures periodically.~~
−	*Example switching output 1 every 10 seconds:
−
−	~~DoPeriod = 10 -- repeat period in seconds~~
−	~~-------------------------------------------------~~
−	~~function doPeriodically()~~
−	~~-- your periodical code~~
−	~~-- your periodical code~~
−	~~-- your periodical code~~
−	~~-- your periodical code~~
−	~~-- your periodical code~~
−	~~-- your periodical code~~
−	~~delay(DoPeriod,function() doPeriodically() end)~~
−	~~end~~
−
−	~~doPeriodically()~~
−
−	*This script can be launch using e.g. [[System started up\|System started up]] trigger.
−	*Only way how to disable these scripts is restart of NETIO~~, or usage of global variables.~~
−
−	~~== Debugging ==~~
−	~~To debug your code, use [[Function log()\|log()]] and [[Function logf()\|logf()]] functions. See the output in system events log.~~
−
−	~~== Data types and variables ==~~
−	~~Lua supports these data types:~~
−	* <i>nil</i> (to assign <i>nil</i> value effectively deletes the variable)
−	* <i>boolean</i> (falsy values are <i>nil</i> and <i>false</i> only; "" and 0 evaluates as <i>true</i>)
−	* <i>number</i> (decimals only in standard Lua, integers only in Netio Lua)
−	* <i>string</i> (same strings share same address, so equality operator measures both address and value)
−	* <i>tables</i> are associative arrays. (Tables with numeric indices are, well, just arrays.)
−
−	~~local numbers = {2,3,7,5} -- array (first index = 1)~~
−	~~local dictionary = {one=1, two=2, three=3} -- table~~
−	~~local numbersZeroBased = {[0]=2,3,7,5} -- array (first index = 0)~~
−
−	<i>local</i> keyword limits the variable scope to the block (ended by <i>end</i>) where it is declared. To access an <i>upvalue</i> (variable defined outside of the scope), just omit the <i>local</i> keyword.
−
−	~~== Operators ==~~
−	~~Lua has its own manners:~~
−	* <code>~=</code> is inequality operator
−	* <code>..</code> is string concatenation (don't use plus)
−	* <code><s>i++</s></code> no increment/decrement operator <code>i = i + 1</code>
−	* <code><s>max = a<b ? b : a</s></code> no ternary operator. Use (and get used to) <i>and idiom</i> instead: <code>max = (a<b) and b or a</code>
−	* <i>or idiom</i> works: <code>x = x or 42</code> is equivalent to <code>if not x then x = 42 end</code>
−
−	~~== Conditions ==~~
−	~~Lua conditions has casual syntax, see [https://www.lua.org/pil/4.3.1.html here~~]~~. Just keep in mind to merge <code>else</code> and <code>if</code> to <code>elseif</code> or multiple <code>end</code>s are required.~~
−
−	~~Note that falsy values are <i>nil</i> and <i>false</i> only. Empty string and 0 evaluates as true. If you come from C, you might be surprised by following snippet:~~
−
−	~~if devices.system.output1_consumption then~~
−	~~-- always happens, even if the consumption is 0~~
−	~~log("Outlet 1 supplies power")~~
−	~~end~~
−
−	~~if not devices.system.output1_consumption then~~
−	~~-- never happens, even if the consumption is 0~~
−	~~log("Outlet 1 is idle")~~
−	~~end~~
−
−	~~== Loops ==~~
−	~~Lua has <code>break</code> statement, but no <code>continue</code> (use condition inside loop instead). Additionally, Netio Lua implementation limits the loop iterations to 32k.~~
−
−	~~=== While ===~~
−	~~While syntax is not different to other languages:~~
−	~~local i = 0~~
−	~~while i~=3 do~~
−	~~i = i + 1~~
−	~~logf("%d",i)~~
−	~~end~~
−
−	~~=== Repeat until ===~~
−	~~Repeat until syntax is the same as Pascal's, other languages have similar do-while loops:~~
−	~~local i = 0~~
−	~~repeat~~
−	~~i = i + 1~~
−	~~logf("%d",i)~~
−	~~until i==3~~
−
−	~~=== Numeric for ===~~
−	~~Arrays in Lua are one-based (in indices are not specified, the first one is 1, not 0).~~
−	~~local arr = {2,3,7,5}~~
−	~~for i=1,#arr do logf("%d",arr[i]) end~~
−	~~<code><b>for</b> initVar,limit,increment <b>do</b></code>~~
−	* <i>number assignment</i> <code>initVar</code> inits loop-local variable
−	* <i>number</i> <code>limit</code> loops until initVar reaches this value
−	* <i>optional number</i> <code>increment</code> after each loop initVar increment by this value (default 1)
−
−	~~=== Generic for ===~~
−	~~Is rather sophisticated. Most common example (the order of elements in <code>pairs()</code> is not guaranteed):~~
−	~~local tab = {one=1, two=2, three=3}~~
−	~~for key,val in pairs(tab) do logf("%s:%d",key,val) end~~
−	~~Generic for syntax~~
−	~~<b>for</b> var_1, ..., var_n <b>in</b> explist <b>do</b> block end~~
−	~~is equivalent to (Full explanation [https://www.lua.org/pil/7.2.html here].)~~
−	do
−	~~local _f, _s, _var = explist~~
−	~~while true do~~
−	~~local var_1, ... , var_n = _f(_s, _var)~~
−	~~_var = var_1~~
−	~~if _var == nil then break end~~
−	~~block~~
−	~~end~~
−	~~end~~
−
−	~~Iterator closure that holds its state~~
−	~~function iter(a)~~
−	~~local i = 0~~
−	~~return function()~~
−	~~i = i+1~~
−	~~return a[i]~~
−	~~end~~
−	~~end~~
−
−	~~local arr = {2,3,7,5}~~
−	~~for value in iter(arr) do~~
−	~~logf("%d",value)~~
−	~~end~~
−
−	~~Stateless iterator (in this case returns variable list: key and value)~~
−	~~function iter(a,i)~~
−	~~i = i+1~~
−	~~if a[i] then return i,a[i] end~~
−	~~end~~
−
−	~~local arr = {2,3,7,5}~~
−	~~for k,v in iter,arr,0 do~~
−	~~logf("%d:%d",k,v)~~
−	~~end~~
−
−	~~Same effect using <code>ipairs()</code> Lua function (without initial state)~~
−	~~for k,v in ipairs(arr) do~~
−	~~logf("%d:%d",k,v)~~
−	~~end~~
−
−	~~Now return to the most common example above using <code>pairs()</code> Lua function and read about <code>pairs()</code> and <code>ipairs()</code> implementation [https://www.lua.org/pil/7.3.html here~~].
−
−	~~== Functions ==~~
−
−	~~Lua allows multiple results (comma separated):~~
−
−	~~function diskSpace()~~
−	~~return devices.system.freeSpace, devices.system.totalSpace~~
−	~~end~~
−
−	~~logf("Free space: %d MB", diskSpace()) -- only first return value is used~~
−	~~local free,total = diskSpace() -- values are stored into LHS var-list~~
−	~~logf("Free space: %d %%", 100*free/total)~~
−
−	~~Variable-length arguments are also available:~~
−
−	~~function sum(...)~~
−	~~local result = 0~~
−	~~for _,v in ipairs(arg) do~~
−	~~result = result + v~~
−	~~end~~
−	~~return result~~
−	~~end~~
−
−	~~logf("Sum: %d", sum(2,3,5))~~

@@ Line 7: / Line 7: @@
   DoPeriod = 10 -- repeat period in seconds
   function doPeriodically()
        -- your periodical code

@@ Line 7: / Line 7: @@
   DoPeriod = 10 -- repeat period in seconds
   function doPeriodically()
        -- your periodical code

@@ Line 3: / Line 3: @@
 == Periodical scipts ==
-In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds) usng standard triggers. For such scripts the trigger  a function [[delay()|delay()]] must be used. This function calls itself and allows to run some procedures periodically.
+In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds) usng standard triggers. For such scripts the trigger [[System started up|System started up]] and the function [[delay()|delay()]] must be used. This function calls itself and allows to run some procedures periodically.
 *Example switching output 1 every 10 seconds:

@@ Line 3: / Line 3: @@
 == Periodical scipts ==
-In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds). For such scripts a function [[delay()|delay()]] must be used. This function allows to run some procedures periodically.
+In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds) usng standard triggers. For such scripts the trigger  a function [[delay()|delay()]] must be used. This function calls itself and allows to run some procedures periodically.
 *Example switching output 1 every 10 seconds:
-  function switch()
-   if devices.system.output1_state == 'on' then
+ DoPeriod = 10 -- repeat period in seconds
-     devices.system.SetOut{output=1,value=false}
-   else
+  function doPeriodically()
-     devices.system.SetOut{output=1, value=true}
+      -- your periodical code
-   end
+      -- your periodical code
-    delay(10,function() switch() end)
+      -- your periodical code
   end
-  switch()
+  doPeriodically()
 *This script can be launch using e.g. [[System started up|System started up]] trigger.

← Older revision		Revision as of 16:21, 11 July 2019
Line 1:		Line 1:
−	== ~~LUA script~~ starting ==	+	== Script starting ==
	LUA Scripts in NETIO are event driven. That means if some [[NETIO Lua Reference\| event]] is triggered the script run exactly once. One of "triggers" is for example [[System started up\|System started up]]. You can find list of all events called "triggers" in [[NETIO Lua Reference\|NETIO Lua Reference]].		LUA Scripts in NETIO are event driven. That means if some [[NETIO Lua Reference\| event]] is triggered the script run exactly once. One of "triggers" is for example [[System started up\|System started up]]. You can find list of all events called "triggers" in [[NETIO Lua Reference\|NETIO Lua Reference]].

@@ Line 1: / Line 1: @@
-== Script triggering ==
+== LUA script starting ==
-Scripts in NETIO are launched with "triggers" such as [[System started up|System started up]]. List of all triggers is in [[NETIO Lua Reference|NETIO Lua Reference]].
+LUA Scripts in NETIO are event driven. That means if some [[NETIO Lua Reference| event]] is triggered the script run exactly once. One of "triggers" is for example [[System started up|System started up]]. You can find list of all events called "triggers" in [[NETIO Lua Reference|NETIO Lua Reference]].
 == Periodical scipts ==

← Older revision		Revision as of 15:50, 11 July 2019
Line 17:		Line 17:

	*This script can be launch using e.g. [[System started up\|System started up]] trigger.		*This script can be launch using e.g. [[System started up\|System started up]] trigger.
		+	*Only way how to disable these scripts is restart of NETIO, or usage of global variables.

	== Debugging ==		== Debugging ==

← Older revision		Revision as of 15:49, 11 July 2019
Line 1:		Line 1:
		+	== Script triggering ==
		+	Scripts in NETIO are launched with "triggers" such as [[System started up\|System started up]]. List of all triggers is in [[NETIO Lua Reference\|NETIO Lua Reference]].
		+
		+	== Periodical scipts ==
		+	In NETIO there is no way for triggering scripts periodically (e.g. every 10 seconds). For such scripts a function [[delay()\|delay()]] must be used. This function allows to run some procedures periodically.
		+	*Example switching output 1 every 10 seconds:
		+	function switch()
		+	if devices.system.output1_state == 'on' then
		+	devices.system.SetOut{output=1,value=false}
		+	else
		+	devices.system.SetOut{output=1, value=true}
		+	end
		+	delay(10,function() switch() end)
		+	end
		+
		+	switch()
		+
		+	*This script can be launch using e.g. [[System started up\|System started up]] trigger.
		+
	== Debugging ==		== Debugging ==
	To debug your code, use [[Function log()\|log()]] and [[Function logf()\|logf()]] functions. See the output in system events log.		To debug your code, use [[Function log()\|log()]] and [[Function logf()\|logf()]] functions. See the output in system events log.

← Older revision		Revision as of 08:34, 6 May 2017
Line 14:		Line 14:
	local numbersZeroBased = {[0]=2,3,7,5} -- array (first index = 0)		local numbersZeroBased = {[0]=2,3,7,5} -- array (first index = 0)

		+	<i>local</i> keyword limits the variable scope to the block (ended by <i>end</i>) where it is declared. To access an <i>upvalue</i> (variable defined outside of the scope), just omit the <i>local</i> keyword.

	== Operators ==		== Operators ==