Programming abstractions in C閱讀筆記p111-p113: boilerplate

《Programming Abstractions In C》學習第47天，p111-p113，總結如下：

一、技術總結
1.boilerplate

/*
 * File: random.h
 * Version: 1.0
 * Last modified on Fri Jul 22 16:44:36 1994 by eroberts
 * -----------------------------------------------------
 * This interface provides several functions for generating
 * pseudo-random numbers.
 */

#ifndef _random_h
#define _random_h

#include "genlib.h"
#include <stdlib.h>

/*
 * Constant: RAND_MAX
 * ------------------
 * Unfortunately, several libraries that supposedly conform to
 * the ANSI standard do not define RAND_MAX in <stdlib.h>.  To
 * reduce portability problems, this interface defines RAND_MAX
 * to be the largest positive integer if it is undefined.
 */

#ifndef RAND_MAX
#  define RAND_MAX ((int) ((unsigned) ~0 >> 1))
#endif

/*
 * Function: Randomize
 * Usage: Randomize();
 * -------------------
 * This function sets the random seed so that the random sequence
 * is unpredictable.  During the debugging phase, it is best not
 * to call this function, so that program behavior is repeatable.
 */

void Randomize(void);

/*
 * Function: RandomInteger
 * Usage: n = RandomInteger(low, high);
 * ------------------------------------
 * This function returns a random integer in the range low to high,
 * inclusive.
 */

int RandomInteger(int low, int high);

/*
 * Function: RandomReal
 * Usage: d = RandomReal(low, high);
 * ---------------------------------
 * This function returns a random real number in the half-open
 * interval [low .. high), meaning that the result is always
 * greater than or equal to low but strictly less than high.
 */

double RandomReal(double low, double high);

/*
 * Function: RandomChance
 * Usage: if (RandomChance(p)) . . .
 * ---------------------------------
 * The RandomChance function returns TRUE with the probability
 * indicated by p, which should be a floating-point number between
 * 0 (meaning never) and 1 (meaning always).  For example, calling
 * RandomChance(.30) returns TRUE 30 percent of the time.
 */

bool RandomChance(double p);

#endif

p113，These three lines are often referred to as interface boilerplate。boilerplate這個詞會在計算機相關的教材中會經常看到，英文的意思是：“text that can be copied and used in computer program，with only small changes.”(模板)，之所以叫模板，是因為在每個頭文件中都有這三句。這個單詞不難理解，關鍵是通過此次的教材對這個單詞有一個具體的、形象的記錄，當提到這個單詞，就知道具體指的是什么。

二、英語總結

1.roll a die一句里面的die是什么意思？
答：die: n.a small cube with a different number of spots on each side.(骰子)，所以roll a die的就是"擲骰子"。

2.along with語法
答：along with在表示伴隨、以及或連同等意思時，兩者之間無先后順序，可能在前也可能在后。這點與follow不同。示例：For each of these functions, the interface contains one-line prototype along with a comment that describe the purpose of the function from the perspective of clients.

3.up to 語法
答：原文：The line:

#ifndef _random_h

cause the compiler to skip any text up to the #endif line if the the symbol _random_h has been previously defined。
up to短語主要有兩種用法：
(1)adv. used to say that sth is less than or equal to but not more than a stated value。
(2)adv. until。
都表示的是“程度”，而不是“方向”。

三、參考資料
1.編程
1)Eric S.Roberts，《Programming Abstractions in C》：https://book.douban.com/subject/2003414
2.英語
1)Etymology Dictionary：https://www.etymonline.com
2)Cambridage Dictionary：https://dictionary.cambridge.org

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