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goto statement

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Flow control
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Jump statements
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goto statement
return statement
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Assembly embutido
 
transfere o controle para um novo local.
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Transfers control to a new location.
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Usado quando é impossível de se transferir o controle para o local desejado usando construções convencionais.
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Used when it is otherwise impossible to transfer control to the desired location using conventional constructs.
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Índice

[editar] Sintaxe

goto label

[editar] Explicação

A instrução goto transfere o controle para o local especificado pelo label. A instrução goto deve estar em a mesma função que o label ele está se referindo. Se as transferências instrução goto controlar para trás, todos os objetos que ainda não foram inicializados no label são destruídas. É ilegal a transferência de controle para a frente, se isso iria pular inicialização de um objeto.
Original:
The goto statement transfers control to the location specified by label. The goto statement must be in the same function as the label it is referring. If goto statement transfers control backwards, all objects that are not yet initialized at the label are destructed. It is illegal to transfer control forwards if doing so would skip initialization of an object.
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[editar] Palavras-chave

goto

[editar] Exemplo

#include <iostream>
 
struct Object {
    ~Object() { std::cout << "d"; }
};
 
int main()
{
    int a = 10;
 
    //loop using goto
label:
    Object obj;
    std::cout << a << " ";
    a = a - 2;
 
    if (a != 0) {
        goto label;  //causes obj to be destructed
    }
    std::cout << '\n';
 
    //get out of multi-level loop easily
    for (int x = 0; x < 3; x++) {
        for (int y = 0; y < 3; y++) {
            std::cout << "(" << x << ";" << y << ") " << '\n';
            if (x + y >= 3) {
                goto endloop;
            }
        }
    }
endloop:
    std::cout << '\n';
 
    return 0;  //causes obj to be destructed
}

Saída:

10 d8 d6 d4 d2
(0;0) (0;1) (0;2) (1;0) (1;1) (1;2)
d