mirror of
https://github.com/adambard/learnxinyminutes-docs.git
synced 2025-08-13 18:24:39 +02:00
Edits
This commit is contained in:
Adam
126
c.html.markdown
126
c.html.markdown
@@ -1,11 +1,9 @@
|
||||
---
|
||||
- name: c
|
||||
- category: language
|
||||
- language: c
|
||||
- filename: learnc.c
|
||||
- contributors:
|
||||
- [Adam Bard](http://adambard.com/)
|
||||
- [Árpád Goretity](http://twitter.com/H2CO3_iOS)
|
||||
language: c
|
||||
filename: learnc.c
|
||||
contributors:
|
||||
- ["Adam Bard", "http://adambard.com/"]
|
||||
- ["Árpád Goretity", "http://twitter.com/H2CO3_iOS"]
|
||||
|
||||
---
|
||||
|
||||
@@ -27,17 +25,10 @@ Multi-line comments look like this. They work in C89 as well.
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
|
||||
// file names between <angle brackets> are headers from the C standard library.
|
||||
// They are searched for by the preprocessor in the system include paths
|
||||
// (usually /usr/lib on Unices, can be controlled with the -I<dir> option if you are using GCC or clang.)
|
||||
// (File names between <angle brackets> are headers from the C standard library.)
|
||||
// For your own headers, use double quotes instead of angle brackets:
|
||||
#include "my_header.h"
|
||||
|
||||
// The C preprocessor introduces an almost fully-featured macro language. It's useful, but
|
||||
// it can be confusing (and what's even worse, it can be misused). Read the
|
||||
// Wikipedia article on the C preprocessor for further information:
|
||||
// http://en.wikipedia.org/wiki/C_preprocessor
|
||||
|
||||
// Declare function signatures in advance in a .h file, or at the top of
|
||||
// your .c file.
|
||||
void function_1();
|
||||
@@ -55,10 +46,6 @@ int main() {
|
||||
// Types
|
||||
///////////////////////////////////////
|
||||
|
||||
// You have to declare variables before using them. A variable declaration
|
||||
// requires you to specify its type; a variable's type determines its size
|
||||
// in bytes.
|
||||
|
||||
// ints are usually 4 bytes
|
||||
int x_int = 0;
|
||||
|
||||
@@ -80,30 +67,23 @@ int main() {
|
||||
// doubles are usually 64-bit floating-point numbers
|
||||
double x_double = 0.0;
|
||||
|
||||
// Integral types may be unsigned. This means they can't be negative, but
|
||||
// the maximum value of an unsigned variable is greater than the maximum
|
||||
// signed value of the same size.
|
||||
unsigned char ux_char;
|
||||
// Integral types may be unsigned.
|
||||
unsigned short ux_short;
|
||||
unsigned int ux_int;
|
||||
unsigned long long ux_long_long;
|
||||
|
||||
// Other than char, which is always 1 byte (but not necessarily 8 bits!),
|
||||
// these types vary in size depending on your machine and compiler.
|
||||
// sizeof(T) gives you the size of a variable with type T in
|
||||
// bytes so you can express the size of these types in a portable way.
|
||||
// sizeof(obj) yields the size of an actual expression (variable, literal, etc.).
|
||||
// For example,
|
||||
// sizeof(T) gives you the size of a variable with type T in bytes
|
||||
// sizeof(obj) yields the size of the expression (variable, literal, etc.).
|
||||
printf("%zu\n", sizeof(int)); // => 4 (on most machines with 4-byte words)
|
||||
|
||||
|
||||
// It's worth noting that if the argument of the `sizeof` operator is not a type but an expression,
|
||||
// then its argument is not evaluated except VLAs (see below). Also, `sizeof()` is an operator, not a function,
|
||||
// furthermore, the value it yields is a compile-time constant (except when used on VLAs, again.)
|
||||
// If the argument of the `sizeof` operator an expression, then its argument
|
||||
// is not evaluated (except VLAs (see below)).
|
||||
// The value it yields in this case is a compile-time constant.
|
||||
int a = 1;
|
||||
size_t size = sizeof(a++); // a++ is not evaluated
|
||||
printf("sizeof(a++) = %zu where a = %d\n", size, a);
|
||||
// the above code prints "sizeof(a++) = 4 where a = 1" (on a usual 32-bit architecture)
|
||||
// prints "sizeof(a++) = 4 where a = 1" (on a 32-bit architecture)
|
||||
|
||||
// Arrays must be initialized with a concrete size.
|
||||
char my_char_array[20]; // This array occupies 1 * 20 = 20 bytes
|
||||
@@ -122,18 +102,21 @@ int main() {
|
||||
my_array[1] = 2;
|
||||
printf("%d\n", my_array[1]); // => 2
|
||||
|
||||
// In C99 (and as an optional feature in C11), variable-length arrays (VLAs) can be declared as well.
|
||||
// The size of such an array need not be a compile time constant:
|
||||
// In C99 (and as an optional feature in C11), variable-length arrays (VLAs)
|
||||
// can be declared as well. The size of such an array need not be a compile
|
||||
// time constant:
|
||||
printf("Enter the array size: "); // ask the user for an array size
|
||||
char buf[0x100];
|
||||
fgets(buf, sizeof buf, stdin);
|
||||
size_t size = strtoul(buf, NULL, 10); // strtoul parses a string to an unsigned integer
|
||||
|
||||
// strtoul parses a string to an unsigned integer
|
||||
size_t size = strtoul(buf, NULL, 10);
|
||||
int var_length_array[size]; // declare the VLA
|
||||
printf("sizeof array = %zu\n", sizeof var_length_array);
|
||||
|
||||
// A possible outcome of this program may be:
|
||||
Enter the array size: 10
|
||||
sizeof array = 40
|
||||
// > Enter the array size: 10
|
||||
// > sizeof array = 40
|
||||
|
||||
// Strings are just arrays of chars terminated by a NUL (0x00) byte,
|
||||
// represented in strings as the special character '\0'.
|
||||
@@ -142,21 +125,13 @@ int main() {
|
||||
char a_string[20] = "This is a string";
|
||||
printf("%s\n", a_string); // %s formats a string
|
||||
|
||||
/*
|
||||
You may have noticed that a_string is only 16 chars long.
|
||||
Char #17 is the NUL byte.
|
||||
Chars #18, 19 and 20 are 0 as well - if an initializer list (in this case, the string literal)
|
||||
has less elements than the array it is initializing, then excess array elements are implicitly
|
||||
initialized to zero. This is why int ar[10] = { 0 } works as expected intuitively.
|
||||
*/
|
||||
|
||||
printf("%d\n", a_string[16]); // => 0
|
||||
// i.e., byte #17 is 0 (as are 18, 19, and 20)
|
||||
|
||||
// So string literals are strings enclosed within double quotes, but if we have characters
|
||||
// between single quotes, that's a character literal.
|
||||
// If we have characters between single quotes, that's a character literal.
|
||||
// It's of type `int`, and *not* `char` (for historical reasons).
|
||||
int cha = 'a'; // fine
|
||||
char chb = 'a'; // fine too (implicit conversion from int to char - truncation)
|
||||
char chb = 'a'; // fine too (implicit conversion from int to char)
|
||||
|
||||
///////////////////////////////////////
|
||||
// Operators
|
||||
@@ -171,7 +146,8 @@ int main() {
|
||||
i2 * i1; // => 2
|
||||
i1 / i2; // => 0 (0.5, but truncated towards 0)
|
||||
|
||||
f1 / f2; // => 0.5, plus or minus epsilon - floating-point numbers and calculations are not exact
|
||||
f1 / f2; // => 0.5, plus or minus epsilon
|
||||
// Floating-point numbers and calculations are not exact
|
||||
|
||||
// Modulo is there as well
|
||||
11 % 3; // => 2
|
||||
@@ -211,10 +187,10 @@ int main() {
|
||||
0x01 << 1; // => 0x02 (bitwise left shift (by 1))
|
||||
0x02 >> 1; // => 0x01 (bitwise right shift (by 1))
|
||||
|
||||
// Be careful when shifting signed integers - the following are all undefined behavior:
|
||||
// Be careful when shifting signed integers - the following are undefined:
|
||||
// - shifting into the sign bit of a signed integer (int a = 1 << 32)
|
||||
// - left-shifting a negative number (int a = -1 << 2)
|
||||
// - shifting by an offset which is more than or equal to the width of the type of the LHS:
|
||||
// - shifting by an offset which is >= the width of the type of the LHS:
|
||||
// int a = 1 << 32; // UB if int is 32 bits wide
|
||||
|
||||
///////////////////////////////////////
|
||||
@@ -232,7 +208,8 @@ int main() {
|
||||
// While loops exist
|
||||
int ii = 0;
|
||||
while (ii < 10) {
|
||||
printf("%d, ", ii++); // ii++ increments ii in-place, after yielding its value ("postincrement").
|
||||
printf("%d, ", ii++); // ii++ increments ii in-place
|
||||
// after yielding its value ("postincrement").
|
||||
} // => prints "0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "
|
||||
|
||||
printf("\n");
|
||||
@@ -240,7 +217,8 @@ int main() {
|
||||
int kk = 0;
|
||||
do {
|
||||
printf("%d, ", kk);
|
||||
} while (++kk < 10); // ++kk increments kk in-place, and yields the already incremented value ("preincrement")
|
||||
} while (++kk < 10); // ++kk increments kk in-place, and yields
|
||||
// the already incremented value ("preincrement")
|
||||
// => prints "0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "
|
||||
|
||||
printf("\n");
|
||||
@@ -257,7 +235,7 @@ int main() {
|
||||
switch (some_integral_expression) {
|
||||
case 0: // labels need to be integral *constant* epxressions
|
||||
do_stuff();
|
||||
break; // if you don't break, control flow falls over labels - you usually don't want that.
|
||||
break; // if you don't break, control flow falls over labels
|
||||
case 1:
|
||||
do_something_else();
|
||||
break;
|
||||
@@ -285,9 +263,8 @@ int main() {
|
||||
|
||||
// Types will overflow without warning
|
||||
printf("%d\n", (unsigned char) 257); // => 1 (Max char = 255 if char is 8 bits long)
|
||||
// printf("%d\n", (unsigned char) 257); would be undefined behavior - `char' is usually signed
|
||||
// on most modern systems, and signed integer overflow invokes UB.
|
||||
// Also, for determining the maximal value of a `char`, a `signed char` and an `unisigned char`,
|
||||
|
||||
// For determining the max value of a `char`, a `signed char` and an `unisigned char`,
|
||||
// respectively, use the CHAR_MAX, SCHAR_MAX and UCHAR_MAX macros from <limits.h>
|
||||
|
||||
// Integral types can be cast to floating-point types, and vice-versa.
|
||||
@@ -318,8 +295,9 @@ int main() {
|
||||
|
||||
// To retreive the value at the address a pointer is pointing to,
|
||||
// put * in front to de-reference it.
|
||||
// Note: yes, it may be confusing that '*' is used for _both_ declaring a pointer and dereferencing it.
|
||||
printf("%d\n", *px); // => Prints 0, the value of x, which is what px is pointing to the address of
|
||||
// Note: yes, it may be confusing that '*' is used for _both_ declaring a
|
||||
// pointer and dereferencing it.
|
||||
printf("%d\n", *px); // => Prints 0, the value of x
|
||||
|
||||
// You can also change the value the pointer is pointing to.
|
||||
// We'll have to wrap the de-reference in parenthesis because
|
||||
@@ -328,7 +306,8 @@ int main() {
|
||||
printf("%d\n", *px); // => Prints 1
|
||||
printf("%d\n", x); // => Prints 1
|
||||
|
||||
int x_array[20]; // Arrays are a good way to allocate a contiguous block of memory
|
||||
// Arrays are a good way to allocate a contiguous block of memory
|
||||
int x_array[20];
|
||||
int xx;
|
||||
for (xx = 0; xx < 20; xx++) {
|
||||
x_array[xx] = 20 - xx;
|
||||
@@ -342,7 +321,8 @@ int main() {
|
||||
// it decays into (implicitly converted to) a pointer.
|
||||
// Exceptions: when the array is the argument of the `&` (address-od) operator:
|
||||
int arr[10];
|
||||
int (*ptr_to_arr)[10] = &arr; // &arr is NOT of type `int *`! It's of type "pointer to array" (of ten `int`s).
|
||||
int (*ptr_to_arr)[10] = &arr; // &arr is NOT of type `int *`!
|
||||
// It's of type "pointer to array" (of ten `int`s).
|
||||
// or when the array is a string literal used for initializing a char array:
|
||||
char arr[] = "foobarbazquirk";
|
||||
// or when it's the argument of the `sizeof` or `alignof` operator:
|
||||
@@ -362,7 +342,7 @@ int main() {
|
||||
// may not be true on e. g. embedded systems - the C standard says nothing about it).
|
||||
int *my_ptr = malloc(sizeof(*my_ptr) * 20);
|
||||
for (xx = 0; xx < 20; xx++) {
|
||||
*(my_ptr + xx) = 20 - xx; // my_ptr[xx] = 20-xx would also work here, and it's also more readable
|
||||
*(my_ptr + xx) = 20 - xx; // my_ptr[xx] = 20-xx
|
||||
} // Initialize memory to 20, 19, 18, 17... 2, 1 (as ints)
|
||||
|
||||
// Dereferencing memory that you haven't allocated gives
|
||||
@@ -381,7 +361,8 @@ int main() {
|
||||
const char *my_str = "This is my very own string literal";
|
||||
printf("%c\n", *my_str); // => 'T'
|
||||
|
||||
// This is not the case if the string is an array (potentially initialized with a string literal)
|
||||
// This is not the case if the string is an array
|
||||
// (potentially initialized with a string literal)
|
||||
// that resides in writable memory, as in:
|
||||
char foo[] = "foo";
|
||||
foo[0] = 'a'; // this is legal, foo now contains "aoo"
|
||||
@@ -435,17 +416,17 @@ printf("%s\n", c); // => ".tset a si sihT"
|
||||
typedef int my_type;
|
||||
my_type my_type_var = 0;
|
||||
|
||||
// Structs are just collections of data, the members are allocated sequentially, in the order they are written:
|
||||
// Structs are just collections of data, the members are allocated sequentially,
|
||||
// in the order they are written:
|
||||
struct rectangle {
|
||||
int width;
|
||||
int height;
|
||||
};
|
||||
|
||||
// it's generally not true that sizeof(struct rectangle) == sizeof(int) + sizeof(int) due to
|
||||
// potential padding between the structure members (this is for alignment reasons. Probably won't
|
||||
// happen if all members are of the same type, but watch out!
|
||||
// See http://stackoverflow.com/questions/119123/why-isnt-sizeof-for-a-struct-equal-to-the-sum-of-sizeof-of-each-member
|
||||
// for further information.
|
||||
// It's not generally true that
|
||||
// sizeof(struct rectangle) == sizeof(int) + sizeof(int)
|
||||
// due to potential padding between the structure members (this is for alignment
|
||||
// reasons). [1]
|
||||
|
||||
void function_1()
|
||||
{
|
||||
@@ -473,7 +454,8 @@ int area(rect r)
|
||||
return r.width * r.height;
|
||||
}
|
||||
|
||||
// if you have large structs, you can pass them "by pointer" to avoid copying the whole struct:
|
||||
// if you have large structs, you can pass them "by pointer" to avoid copying
|
||||
// the whole struct:
|
||||
int area(const rect *r)
|
||||
{
|
||||
return r->width * r->height;
|
||||
@@ -527,3 +509,5 @@ Readable code is better than clever code and fast code. For a good, sane coding
|
||||
[Linux kernel coding stlye](https://www.kernel.org/doc/Documentation/CodingStyle).
|
||||
|
||||
Other than that, Google is your friend.
|
||||
|
||||
[1] http://stackoverflow.com/questions/119123/why-isnt-sizeof-for-a-struct-equal-to-the-sum-of-sizeof-of-each-member
|
||||
|
||||
@@ -1,5 +1,6 @@
|
||||
---
|
||||
language: java
|
||||
filename: java-kr.java
|
||||
category: language
|
||||
contributors:
|
||||
- ["Jake Prather", "http://github.com/JakeHP"]
|
||||
@@ -26,7 +27,8 @@ import java.util.ArrayList;
|
||||
// java.security 패키지 안에 있는 모든 클래스를 임포트합니다.
|
||||
import java.security.*;
|
||||
|
||||
// 각 .java 파일에는 공용(public) 클래스가 들어 있으며, 클래스의 이름은 파일명과 동일합니다.
|
||||
// 각 .java 파일에는 공용(public) 클래스가 들어 있으며, 클래스의 이름은
|
||||
// 파일명과 동일합니다.
|
||||
public class LearnJava {
|
||||
|
||||
// 프로그램에는 반드시 진입점 역할을 하는 main 메서드가 하나 있어야 합니다.
|
||||
@@ -253,8 +255,8 @@ public class LearnJava {
|
||||
// String
|
||||
|
||||
// 형변환
|
||||
// 자바 객채 또한 형변환할 수 있으며, 이와 관련해서 알아야 할 세부사항이 많을뿐더러
|
||||
// 다소 중급 수준에 해당하는 개념들도 다뤄야 합니다.
|
||||
// 자바 객채 또한 형변환할 수 있으며, 이와 관련해서 알아야 할 세부사항이
|
||||
// 많을뿐더러 다소 중급 수준에 해당하는 개념들도 다뤄야 합니다.
|
||||
// 이와 관련된 사항은 아래 링크를 참고하세요.
|
||||
// http://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
|
||||
|
||||
|
||||
@@ -1,5 +1,6 @@
|
||||
---
|
||||
language: ruby
|
||||
lang: br-pt
|
||||
filename: learnruby.rb
|
||||
contributors:
|
||||
- ["Bruno Henrique - Garu", "http://garulab.com"]
|
||||
@@ -98,9 +99,10 @@ caminho_para_a_raiz_do_projeto = '/bom/nome/'
|
||||
caminho = '/nome/ruim/'
|
||||
|
||||
# Símbolos (são objetos)
|
||||
# Símbolos são imutáveis, são constantes reutilizáveis representadadas internamente por um
|
||||
# valor inteiro. Eles são frequentemente usados no lugar de strings para transmitir com eficiência os valores
|
||||
# específicos e significativos
|
||||
# Símbolos são imutáveis, são constantes reutilizáveis representadadas
|
||||
# internamente por um valor inteiro. Eles são frequentemente usados no
|
||||
# lugar de strings para transmitir com eficiência os valores específicos
|
||||
# e significativos
|
||||
|
||||
:pendente.class #=> Symbol
|
||||
|
||||
|
||||
@@ -4,7 +4,7 @@ filename: learnclojure-ru.clj
|
||||
contributors:
|
||||
- ["Adam Bard", "http://adambard.com/"]
|
||||
- ["Alexey Pirogov", "http://twitter.com/alex_pir"]
|
||||
|
||||
lang: ru-ru
|
||||
---
|
||||
|
||||
Clojure, это представитель семейства Lisp-подобных языков, разработанный
|
||||
|
||||
@@ -88,7 +88,8 @@ $unescaped = 'This just contains a slash and a t: \t';
|
||||
// Заключайте переменные в фигурные скобки если это необходимо
|
||||
$money = "I have $${number} in the bank.";
|
||||
|
||||
// Начиная с PHP 5.3, синтаксис nowdocs может использоваться для неинтерполированного многострочного текста
|
||||
// Начиная с PHP 5.3, синтаксис nowdocs может использоваться для
|
||||
// неинтерполированного многострочного текста
|
||||
$nowdoc = <<<'END'
|
||||
Multi line
|
||||
string
|
||||
@@ -210,11 +211,13 @@ echo $integer + $integer; // => 2
|
||||
$string = '1';
|
||||
echo $string + $string; // => 2 (строка превращается в число)
|
||||
|
||||
// Выводится 0 по той причине, что оператор + не может привести строку 'one' к числовому типу
|
||||
// Выводится 0 по той причине, что оператор + не может привести строку 'one' к
|
||||
// числовому типу
|
||||
$string = 'one';
|
||||
echo $string + $string; // => 0
|
||||
|
||||
// Приведение типов (type casting) может быть использовано для преобразование переменной в другой тип
|
||||
// Приведение типов (type casting) может быть использовано для преобразование
|
||||
// переменной в другой тип
|
||||
$boolean = (boolean) 1; // => true
|
||||
|
||||
$zero = 0;
|
||||
@@ -429,10 +432,11 @@ return 'Anything you like.';
|
||||
// Эти функции могут также возвращать значения.
|
||||
$value = include 'my-include.php';
|
||||
|
||||
// Имена файлов содержат их путь в файловой системе, или если передано просто имя файла,
|
||||
// PHP обращается к директиве include_path. Если файл не найден в include_path, предпринимается
|
||||
// попытка поиска в папке, где выполняется скрипт или в текущей рабочей директории.
|
||||
// Если не в одном из этих мест файл не найден - выдается ошибка
|
||||
// Имена файлов содержат их путь в файловой системе, или если передано просто
|
||||
// имя файла, PHP обращается к директиве include_path. Если файл не найден в
|
||||
// include_path, предпринимается попытка поиска в папке, где выполняется скрипт
|
||||
// или в текущей рабочей директории. Если не в одном из этих мест файл не
|
||||
// найден - выдается ошибка
|
||||
/* */
|
||||
|
||||
/********************************
|
||||
|
||||
@@ -1,5 +1,6 @@
|
||||
---
|
||||
language: python
|
||||
lang: ru-ru
|
||||
contributors:
|
||||
- ["Yury Timofeev", "http://twitter.com/gagar1n"]
|
||||
filename: learnpython-ru.py
|
||||
@@ -219,7 +220,8 @@ filled_dict["four"] # KeyError
|
||||
# Чтобы избежать этого, используйте метод get
|
||||
filled_dict.get("one") #=> 1
|
||||
filled_dict.get("four") #=> None
|
||||
# Метод get также принимает аргумент default, значение которого будет возвращено при отсутствии указанного ключа
|
||||
# Метод get также принимает аргумент default, значение которого будет
|
||||
# возвращено при отсутствии указанного ключа
|
||||
filled_dict.get("one", 4) #=> 1
|
||||
filled_dict.get("four", 4) #=> 4
|
||||
|
||||
@@ -314,7 +316,9 @@ try:
|
||||
# Для выбора ошибки используется raise
|
||||
raise IndexError("Это IndexError")
|
||||
except IndexError as e:
|
||||
pass # pass это просто отсутствие оператора. Обычно здесь происходит восстановление от ошибки.
|
||||
# pass это просто отсутствие оператора. Обычно здесь происходит
|
||||
# восстановление от ошибки.
|
||||
pass
|
||||
|
||||
|
||||
####################################################
|
||||
|
||||
@@ -29,7 +29,8 @@ import (
|
||||
"strconv" // 字符串转换
|
||||
)
|
||||
|
||||
//函数声明：Main是程序执行的入口。不管你喜欢还是不喜欢，反正G就用了花括号来包住函数体。
|
||||
// 函数声明：Main是程序执行的入口。
|
||||
// 不管你喜欢还是不喜欢，反正G就用了花括号来包住函数体。
|
||||
func main() {
|
||||
// 往标准输出打印一行。
|
||||
// 用包名fmt限制打印函数。
|
||||
@@ -125,7 +126,8 @@ func learnFlowControl() {
|
||||
if true {
|
||||
fmt.Println("told ya")
|
||||
}
|
||||
// 用go fmt 命令可以帮你格式化代码，所以不用怕被人吐槽代码风格了，也不用容忍被人的代码风格。
|
||||
// 用go fmt 命令可以帮你格式化代码，所以不用怕被人吐槽代码风格了，
|
||||
// 也不用容忍被人的代码风格。
|
||||
if false {
|
||||
// pout
|
||||
} else {
|
||||
@@ -196,7 +198,8 @@ func learnInterfaces() {
|
||||
// 调用i的String方法，输出和上面一样
|
||||
fmt.Println(i.String())
|
||||
|
||||
// fmt包中的Println函数向对象要它们的string输出，实现了String方法就可以这样使用了。（类似java中的序列化）
|
||||
// fmt包中的Println函数向对象要它们的string输出，实现了String方法就可以这样使用了。
|
||||
// （类似java中的序列化）
|
||||
fmt.Println(p) // 输出和上面一样，自动调用String函数。
|
||||
fmt.Println(i) // 输出和上面一样。
|
||||
|
||||
@@ -229,7 +232,8 @@ func inc(i int, c chan int) {
|
||||
func learnConcurrency() {
|
||||
// 用make来声明一个slice，make会分配和初始化slice，map和channel。
|
||||
c := make(chan int)
|
||||
// 用go关键字开始三个并发的goroutine，如果机器支持的话，还可能是并行执行。三个都被发送到同一个channel。
|
||||
// 用go关键字开始三个并发的goroutine，如果机器支持的话，还可能是并行执行。
|
||||
// 三个都被发送到同一个channel。
|
||||
go inc(0, c) // go is a statement that starts a new goroutine.
|
||||
go inc(10, c)
|
||||
go inc(-805, c)
|
||||
@@ -241,7 +245,8 @@ func learnConcurrency() {
|
||||
cc := make(chan chan string) // 操作channel的channel
|
||||
go func() { c <- 84 }() // 开始一个goroutine来发送一个新的数字
|
||||
go func() { cs <- "wordy" }() // 发送给cs
|
||||
// Select类似于switch，但是每个case包括一个channel操作。它随机选择一个准备好通讯的case。
|
||||
// Select类似于switch，但是每个case包括一个channel操作。
|
||||
// 它随机选择一个准备好通讯的case。
|
||||
select {
|
||||
case i := <-c: // 从channel接收的值可以赋给其他变量
|
||||
fmt.Println("it's a", i)
|
||||
|
||||
Reference in New Issue
Block a user