What is the difference between lua and javascript-Front-end Q&A-php.cn

What is the difference between lua and javascript

WBOY

Release： 2022-01-19 16:04:26

original

3644 people have browsed it

Difference: 1. The comment code of JavaScript is "//", and the comment code of Lua is "--"; 2. JavaScript uses val to declare global variables and there are no local variables, while Lua does not need to be directly positioned. are global variables, and local declarations are local variables.

What is the difference between lua and javascript

The operating environment of this tutorial: Windows 10 system, JavaScript version 1.8.5, Dell G3 computer.

What is the difference between lua and javascript

Comparison of the differences between Lua and Javascript

Lua simulator js solution

1. Syntax level simulation

Differences between lua and js language

1.1 Comments

js is //, lua is --.

1.2 Variables

js uses val to declare global variables and there are no local variables, while lua does not need to be positioned directly. are global variables, and local declarations are local variables.

1.3 Operator

- * / % --

= = -= *= /= %=

Supported strings

txt1 = "what a very";

txt2 = "nice day";

txt3 =txt1 " " txt2;

The output result of printing txt3 is "what a very nice day".

Rule:

Compare numbers with strings Add, the result will become a string.

binary: - * / ^ %

uniary:- (Minus sign)

lua strings are spliced into ..

For example, "Hello ".."World" is spliced into Hello World

1.4 Relational Operator

js relational operator

== === (congruent) != > < >= < =

lua relational operator

##< > <= >= == ~=(not equal to)

1.5 Logical operators

1.6 If ...Else statement

if then

elseif then

else

end

There must be end

1.7 Switch statement

lua does not support Switch statement

1.8 Message box

Confirm box prompt("text","default value")

1.9 Function

##js

function 函数名(参数)
{
　　代码．．．
}

Copy after login

js with {} class c

lua

```
function 函数名( 参数)
end
```
Copy after login
lua class vb script

2.0 For loop

js: Class c

for (i=0;i<=10;i++)
{
  document.write("The number is " + i)
  document.write("
")
}

Copy after login

lua: divided into two types: numeric type For and generic For

numeric type For:

for var= exp1,exp2,exp3 do
<执行体>
end

Copy after login

var changes from exp1 to exp2, step is incremented by exp3

If exp3 is not specified, the default is 1

for i =1,100 do 
print(i)
end
for i =1,100,2 do 
print(i)
end

Copy after login

Generic For

The generic For loop traverses all values through an iterator (iterator) function :

--打印数组a 的所有值
for i,v in pairs(a) do print(v) end

Copy after login

The Lua basic library provides ipairs, which is an iterator function for traversing arrays.

In each loop i will be assigned an index value, and v will be assigned an array element value corresponding to

the index.

---打印table t中所以的key
for k in pairs(t) do print(k) end

Copy after login

2.1 While loop

js: Class c

while (变量<=结束值)
{
    需执行的代码
}
lua:
i =1;
while a[i] do
print(a[i])
i = i+1;
end

Copy after login

At the same time, lua also supports repeat: supports repeat-until statement to implement loop.

repeat:
 line = io.read()
until line~=""
print(line)

Copy after login

The above code: Read line until the end when line is not "", and print the value of this line.

2.2 Break and Continue

js: There are two types of c

that can be used in loops Statements in: break and continue

Break

The break command can terminate the running of the loop and then continue to execute the code after the loop (if there is code after the loop).

Code example:


Continue

Copy after login

continue command will terminate the current loop and continue running from the next value.

Copy after login

Lua:

supports break, but does not support continue.

local i =1
while a[i] do
 if a[i] == v then break end
 i = i +1
end

Copy after login

2.3 For... In statement

js: Use the For...In statement to specifically traverse the elements in the array.

For...In statement is used to loop through the properties of an array or object.

for ... in Each time the code in the loop is executed, an operation will be performed on the elements of the array or the properties of the object.

Syntax:

for (变量 in 对象)
{
    在此执行代码
}

Copy after login

Code:

Copy after login

Lua: It is very simple to replace it with the generic For.

Related recommendations:

javascript learning tutorial

The above is the detailed content of What is the difference between lua and javascript. For more information, please follow other related articles on the PHP Chinese website!