64 lines
1.3 KiB
Markdown
64 lines
1.3 KiB
Markdown
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---
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title: Short-Circuit Evaluation
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localeTitle: Evaluación de corto circuito
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---
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# Evaluación de corto circuito
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La evaluación de cortocircuito consiste en verificar o ejecutar el segundo argumento solo si el primer argumento no es suficiente para determinar el valor de la expresión.
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Puede hacer una evaluación de cortocircuito con && y || operadores
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## Ejemplo con el operador &&:
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```c
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canOpenFile(filename) && openFile(filename); // If you can open the file then open it.
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```
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El ejemplo anterior es equivalente a:
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```c
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if ( canOpenFile(filename) ) {
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openFile(filename);
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}
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```
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## Ejemplo con || operador:
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```c
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isServerOn || startServer(); // If the server is not on then start it.
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```
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The example above is equivalent to:
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```c
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if ( !isServerOn ) {
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startServer();
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}
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```
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## Keep it all together in real example
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```c
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#include <stdio.h>
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#include <stdlib.h>
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char *getName();
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int main(int argc, char *argv[]) {
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// Get first argument passed via terminal
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char *name = argv[1];
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// If name is not passed via terminal then print message and then get the name
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name || printf("Please give me your name:") && (name = getName());
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printf("Hello %s\n", name);
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}
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char *getName() {
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// Allocate memory
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char *name = malloc(30);
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scanf("%s", name);
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return name;
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}
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```
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