to and from the stack, as well as functions for manipulating tables through the stack. -- A simplified way of writing when the index is string, -- Using index access is essentially a function call like this, --The following example loops out the value of a in the chat box. If you use loop nesting, the break statement will stop the execution of the innermost loop and start the execution of the outer loop. The factorial function is implemented as a function in this example: Lua has four types of loops: the while loop, the repeat loop (similar to a do while loop), the numeric for loop, and the generic for loop. The article is about the Lua programming language itself. Support procedure-oriented and functional programming); Automatic memory management; Only one generic type of table is provided, which can implement arrays, hash tables, collections and objects; Language built-in pattern matching;Closure; The function can also be viewed as a value; Support for multi-threading (collaborative processes, not threads supported by the operating system); Closures and tables make it easy to support some of the key mechanisms required for object-oriented programming, such as data abstraction, virtual functions, inheritance, and overloading. She's really great! A key (index) can be any value except nil and NaN, including functions. check if the value on the left is greater than the value on the right. Before the compiler can execute the code, it needs to know how to store the values of the statement variables. -- Prints 4. In other words, a variable only exists when it is not equal to nil. is dynamically typed, Similarly, Lua allows programmers to implement namespaces, classes, and other related features using its single table implementation; first-class functions allow the employment of many techniques from functional programming; and full lexical scoping allows fine-grained information hiding to enforce the principle of least privilege. An identifier begins with letter A to Z or a to z or an underscore _ followed by 0 or more letters, underscores, and Numbers (0 to 9). For its use in Wikipedia, see, --delta may be negative, allowing the for loop to count down or up, -- Store current print function as oldprint, --[[ Redefine print function. Answer for If there is no app in the mobile phone, it will jump to the app related app. Lua syntax for control structures was mostly borrowed from Modula (if, while, repeat/until), but also had taken influence from CLU (multiple assignments and multiple returns from function calls, as a simpler alternative to reference parameters or explicit pointers), C++ ("neat idea of allowing a local variable to be declared only where we need it"[5]), SNOBOL and AWK (associative arrays). Those reasons led Tecgraf to implement the basic tools it needed from scratch.[5]. Lua's treatment of functions as first-class values is shown in the following example, where the print function's behavior is modified: Any future calls to print will now be routed through the new function, and because of Lua's lexical scoping, the old print function will only be accessible by the new, modified print.