Also, sort is generic, so that it can be used for any reasonable combination of container type, element type, and comparison criterion.
A function definition is an executable expression, whose value has type function. When Lua pre-compiles a chunk, all its function bodies are pre-compiled too.
Then, whenever Lua executes the function definition, the function is instantiated or closed. This function instance or closure is the final value of the expression. Different instances of the same function can refer to different external local variables and can have different environment tables.
Parameters act as local variables that are initialized with the argument values: A vararg function does not adjust its argument list; instead, it collects all extra arguments and supplies them to the function through a vararg expression, which is also written as three dots.
The value of this expression is a list of all actual extra arguments, similar to a function with multiple results.
If a vararg expression is used inside another expression or in the middle of a list of expressions, then its return list is adjusted to one element. If the expression is used as the last element of a list of expressions, then no adjustment is made unless that last expression is enclosed in parentheses.
As an example, consider the following definitions: If control reaches the end of a function without encountering a return statement, then the function returns with no results. The colon syntax is used for defining methods, that is, functions that have an implicit extra parameter self.
Thus, the statement function t. The scope of variables begins at the first statement after their declaration and lasts until the end of the innermost block that includes the declaration.
Consider the following example: Because of the lexical scoping rules, local variables can be freely accessed by functions defined inside their scope. A local variable used by an inner function is called an upvalue, or external local variable, inside the inner function.
Notice that each execution of a local statement defines new local variables. Each of these closures uses a different y variable, while all of them share the same x. Whenever an error occurs during Lua compilation or execution, control returns to C, which can take appropriate measures such as printing an error message.
Lua code can explicitly generate an error by calling the error function.
If you need to catch errors in Lua, you can use the pcall function. This metatable is an ordinary Lua table that defines the behavior of the original value under certain special operations. You can change several aspects of the behavior of operations over a value by setting specific fields in its metatable.
If it finds one, Lua calls this function to perform the addition. We call the keys in a metatable events and the values metamethods. In the previous example, the event is "add" and the metamethod is the function that performs the addition.
You can query the metatable of any value through the getmetatable function. You can replace the metatable of tables through the setmetatable function.
Tables and full userdata have individual metatables although multiple tables and userdata can share their metatables. Values of all other types share one single metatable per type; that is, there is one single metatable for all numbers, one for all strings, etc.
A metatable controls how an object behaves in arithmetic operations, order comparisons, concatenation, length operation, and indexing. A metatable also can define a function to be called when a userdata is garbage collected.The C Program is written for implementation of STACK using Array, the basic operations of stack are PUSH(), POP() and DISPLAY().
PUSH function in the code is used to insert an element to the top of stack, POP function used to remove the element from the top of stack. C program to reverse a number: This program reverses the number entered by the user and then print it on the screen.
For example, if a user will enter as input then will be printed as output.
In our program, we use modulus (%) operator to . /*A C program is executed as if it is a function called by the Operating System, the Operating System can and does pass parameters to the program.
lua_createtable [-0, +1, m] void lua_createtable (lua_State *L, int narr, int nrec); Creates a new empty table and pushes it onto the stack.
The new table has space pre-allocated for narr array elements and nrec non-array elements. This pre-allocation is useful when . Write a recursive program to efficiently reverse a given string in C, C++ and Java. As seen in the previous post, we can easily reverse a string using stack data structure.
As stack is involved, we can easily convert the code to use function call stack. The time complexity of the solution is O(n) and total space used. The C++ Core Guidelines are a set of tried-and-true guidelines, rules, and best practices about coding in C++.