Difference between revisions of "Basic lua: Types"

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(Created page with "Lua operators are expressions used to perform calculations or to pass arguments between different value types. {| class="in" |- | class="i_arrow clickablecell" | basic_lua:...")
 
 
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Lua operators are expressions used to perform calculations or to pass arguments between different value types.
 
 
{| class="in"
 
{| class="in"
 
|-
 
|-
−
| class="i_arrow clickablecell" |  [[basic_lua:_Index|<]]
+
| class="i_arrow clickablecell" |  [[basic_lua:_Operators|<]]
 
| class="i_norm clickablecell" | '''[[basic_lua:_Index|Index]]'''
 
| class="i_norm clickablecell" | '''[[basic_lua:_Index|Index]]'''
−
| class="i_arrow clickablecell" | [[basic_lua:_Types|>]]
+
| class="i_arrow clickablecell" | [[basic_lua:_Tables|>]]
 
|}
 
|}
−
== Conditional Operators ==
+
<hr>
−
{| class="ts"
+
There are multiple lua types available, which are automatically determined by the returned value of the variable, function or table.
−
|-
 
−
| if || width="90%" | Query if something does or does not meet a certain condition.
 
−
|-
 
−
| else || Do something else if the query condition was not met.
 
−
|-
 
−
| elseif || Used to add additional if queries, if the initial query condition was not met.
 
−
|-
 
−
| end || This is used to close various queries or functions; there must be the same amount of '''end''' as '''if'''; except in instances where '''elseif''' has been used.
 
−
|}
 
  
 +
== Types ==
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
!  Example 1: if condition is true (method 1) !!
+
| <span class="vsyellow">boolean</span> || width="90%" | This returns a value of '''true''' or '''false'''.
−
|-
 
−
| <syntaxhighlight>
 
−
local a = true
 
−
 
 
−
if a then
 
−
print("a = true")
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_001.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 2: if condition is true (method 2) !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = true
 
−
 
 
−
if a == true then
 
−
print("a = true")
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_002.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 3: if condition is false !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = false
 
−
 
 
−
if a == false then
 
−
print("a = false")
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_004.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 4: if condition is not met, then do else !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = false
 
−
 
 
−
if a then
 
−
print("a = true")
 
−
else
 
−
print("a = false")
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_005.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
 
|-
 
|-
−
! Example 5: if condition is not met, then do elseif !!
+
| <span class="vsyellow">function</span> || A function usually contains a list of actions to be executed & can often be used to calculate & return values.
 
|-
 
|-
−
| <syntaxhighlight>
+
| <span class="vsyellow">nil</span> || If no data type is returned then whatever you queried is either empty or does not exist, thus it is '''nil'''.
−
local a = false
 
−
 
 
−
if a then
 
−
print("a = true")
 
−
elseif not a then
 
−
print("a = false")
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_006.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
== Logical Operators ==
 
−
{| class="ts"
 
 
|-
 
|-
−
| and || width="90%" | Allows you to check multiple conditions in a single if query.
+
| <span class="vsyellow">number</span> || This usually contains an integer (whole) or floating point (decimal) number.
 
|-
 
|-
−
| or || Allows you to add an alternative if query into a single if query.
+
| <span class="vsyellow">string</span> || This usually contains text or numbers wrapped in "quotation marks" or 'apostrophes'.
 
|-
 
|-
−
| not || Checks if condition equals false or negative.
+
| <span class="vsyellow">table</span> || This usually consists of an array, or multiple arrays of data & data types.
 
|}  
 
|}  
  
 +
=== Boolean ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
! Example 1: if condition a is true and condition b is false then !!
+
! prints true !!
 
|-
 
|-
−
| <syntaxhighlight>
+
| <syntaxhighlight lang="lua">
 
local a = true
 
local a = true
−
local b = false
 
  
−
if a == true and b == false then
+
print( a, type(a) )
−
print("a = true", "b=false")
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_1.png|frameless|center|180px]]
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_007.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
  
 +
=== Function ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
! Example 2: if condition is true or condition == true then !!
+
! prints 7 !!
 
|-
 
|-
−
| <syntaxhighlight>
+
| <syntaxhighlight lang="lua">
−
local a = true
+
function a(i)
−
 
+
  return i
−
if a or a == true then
 
−
  print("a = true")
 
 
end
 
end
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_008.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
−
{| class="ts"
 
−
|-
 
−
! Example 3: if condition is not true !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = false
 
  
−
if not a then
+
print( a(7), type(a) )
−
print("a = false")
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_2.png|frameless|center|180px]]
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_003.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
  
−
== Comparison Operators ==
+
=== Nil ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
| <big>==</big> || width="90%" | Equal to.
+
! prints nil, nil !!
 
|-
 
|-
−
| <big>~=</big> || Does not equal.
+
| <syntaxhighlight lang="lua">
−
|-
+
local a = nil
−
| <big>>=</big> || Greater than or equal to.
 
−
|-
 
−
| <big>></big> || Greater than.
 
−
|-
 
−
| <big><=</big> || Less than or equal to.
 
−
|-
 
−
| <big><</big> || Less than.
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
!  Example 1: if a equals 1 !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 1
 
  
−
if a == 1 then
+
print( a, "  type = " .. type(a) )
−
print("a = 1")
+
print( b, " type = " .. type(b) )
−
end
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_3.png|frameless|center|180px]]
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_009.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
  
 +
=== Number ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
! Example 2: if a does not equal 2 !!
+
! prints 7, 7.25 !!
 
|-
 
|-
−
| <syntaxhighlight>
+
| <syntaxhighlight lang="lua">
−
local a = 1
+
local a = 7
 +
local b = 7.25
  
−
if a ~= 2 then
+
print( a, type(a) )
−
print("a = " .. a)
+
print( b, type(b) )
−
end
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_4.png|frameless|center|180px]]
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_010.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
  
 +
=== String ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
! Example 3: if a is greater than or equal to 2 !!
+
! prints hello world !!
 
|-
 
|-
−
| <syntaxhighlight>
+
| <syntaxhighlight lang="lua">
−
local a = 5
+
local a = "hello world"
  
−
if a >= 2 then
+
print( a, type(a) )
−
print("a = " .. a)
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_5.png|frameless|center|180px]]
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_011.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
  
 +
=== Table ===
 
{| class="ts"
 
{| class="ts"
 
|-
 
|-
−
! Example 4: if a is greater than 2 !!
+
! prints 1, 2, 3, 4, 5, 6, 7, 8 !!
 
|-
 
|-
−
| <syntaxhighlight>
+
| <syntaxhighlight lang="lua">
−
local a = 3
+
local a = {1,1+1,1*3,2*2,20/4,"6",3.5*2,10-2}
  
−
if a > 2 then
+
print( a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], type(a) )
−
print("a = " .. a)
+
</syntaxhighlight> || width="180px" style="vertical-align:middle;" | [[File:Basic_lua_(types)_6.png|frameless|center|180px]]
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_012.png|thumb|right|180px|click to enlarge]]
 
 
|}
 
|}
−
 
+
<hr>
−
{| class="ts"
 
−
|-
 
−
! Example 5: if a less than or equal to 2  !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 2
 
−
 
 
−
if a <=  2 then
 
−
print("a = " .. a)
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_013.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 6: if a less than 2  !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 0
 
−
 
 
−
if a <  2 then
 
−
print("a = " .. a)
 
−
end
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_014.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
== Mathematical Operators ==
 
−
{| class="ts"
 
−
|-
 
−
| <big>+</big> || width="90%" | Add
 
−
|-
 
−
| <big>-</big> || Subtract or invert
 
−
|-
 
−
| <big>*</big> || Multiply
 
−
|-
 
−
| <big>/</big> || Divide
 
−
|-
 
−
| <big>^</big> || Power
 
−
|-
 
−
| <big>%</big> || Remainder
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
!  Example 1: 1 +2 = 3 !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 1
 
−
local b = 2
 
−
local result = a + b
 
−
 
 
−
print( result )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_015.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 2: 3 - 2 = 1 !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 3
 
−
local b = 2
 
−
local result = a - b
 
−
 
 
−
print( result )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_016.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 3: inversed values !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 3
 
−
local result = -a
 
−
 
 
−
print( "original value: " .. a, "inversed value: " .. result )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_017.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 4: 2 x 2 = 4 !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 2
 
−
local result = a * a
 
−
 
 
−
print( result )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_018.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 5: 10 ÷ 5 = 2  !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 10
 
−
local b = 5
 
−
local result = a / b
 
−
 
 
−
print( result )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_019.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
! Example 6: base of 2, power of 8 (2ⁿ) = 256  !!
 
−
|-
 
−
| <syntaxhighlight>
 
−
local a = 2
 
−
local b = 8
 
−
local result = 2 ^ 8
 
−
 
 
−
-- break down power function into string result (ignore this code)
 
−
function power(i1, i2)
 
−
local val = ""
 
−
--+--
 
−
for i = 1, i2 do
 
−
  if i < i2 then val = val..i1.."*" else val = val..i1 end
 
−
end
 
−
return "which is the equivalent of " .. val
 
−
end
 
−
 
 
−
print("power value of 2 & 8 = " .. result, power(a,b))
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_020.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
−
{| class="ts"
 
−
|-
 
−
!  Example 7: remainder of 25 ÷ 4 = 1 !!
 
−
|-
 
−
| style="max-width: 700px;" | <syntaxhighlight>
 
−
local a = 25
 
−
local b = 4
 
−
local result = a / 4
 
−
local remainder = a % b
 
−
local decimal = remainder / b
 
−
 
 
−
print("result: 25 ÷ 4 = "  .. result, "remainder: .25 x 4 = " .. remainder, "decimal: 1 ÷ 4 = " .. decimal )
 
−
</syntaxhighlight> || width="200px" | [[File:lb_operators_021.png|thumb|right|180px|click to enlarge]]
 
−
|}
 
−
 
 
 
{| class="in"
 
{| class="in"
 
|-
 
|-
−
| class="i_arrow" |  [[basic_lua:_Index|<]]
+
| class="i_arrow clickablecell" |  [[basic_lua:_Operators|<]]
−
| class="i_norm" | '''[[basic_lua:_Index|Index]]'''
+
| class="i_norm clickablecell" | '''[[basic_lua:_Index|Index]]'''
−
| class="i_arrow" | [[basic_lua:_Types|>]]
+
| class="i_arrow clickablecell" | [[basic_lua:_Tables|>]]
−
|}
+
|}{{toc}}
−
{{toc}}
 

Latest revision as of 03:16, 3 September 2022

< Index >

There are multiple lua types available, which are automatically determined by the returned value of the variable, function or table.

Types

boolean This returns a value of true or false.
function A function usually contains a list of actions to be executed & can often be used to calculate & return values.
nil If no data type is returned then whatever you queried is either empty or does not exist, thus it is nil.
number This usually contains an integer (whole) or floating point (decimal) number.
string This usually contains text or numbers wrapped in "quotation marks" or 'apostrophes'.
table This usually consists of an array, or multiple arrays of data & data types.

Boolean

prints true 
local a = true

print( a, type(a) )
Basic lua (types) 1.png

Function

prints 7 
function a(i)
 return i
end

print( a(7), type(a) )
Basic lua (types) 2.png

Nil

prints nil, nil 
local a = nil

print( a, "  type = " .. type(a) )
print( b, "  type = " .. type(b) )
Basic lua (types) 3.png

Number

prints 7, 7.25 
local a = 7
local b = 7.25

print( a, type(a) )
print( b, type(b) )
Basic lua (types) 4.png

String

prints hello world 
local a = "hello world"

print( a, type(a) )
Basic lua (types) 5.png

Table

prints 1, 2, 3, 4, 5, 6, 7, 8 
local a = {1,1+1,1*3,2*2,20/4,"6",3.5*2,10-2}

print( a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], type(a) )
Basic lua (types) 6.png
< Index >

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