1
00:00:05,500 --> 00:00:09,000
In this video, we'll take a high level look at how all this works.

2
00:00:09,600 --> 00:00:14,100
If you're completely new to programming, then many of these terms will probably be new to you.

3
00:00:15,000 --> 00:00:18,500
The most important thing to remember is that the computer isn't smart at all.

4
00:00:19,000 --> 00:00:22,300
It simply does exactly what it's told to do by the programmer,

5
00:00:22,800 --> 00:00:24,400
and the programmer in this case is you.

6
00:00:25,200 --> 00:00:27,200
A computer program is like a recipe.

7
00:00:27,200 --> 00:00:31,700
If you want to bake a cake, there are a series of tasks that you must execute in a specific order,

8
00:00:32,000 --> 00:00:34,500
otherwise the final product won't be a cake.

9
00:00:35,000 --> 00:00:38,300
Suppose that one of the tasks is to put four eggs in a bowl and mix.

10
00:00:38,600 --> 00:00:41,900
A human might assume that the number of eggs need to be cracked

11
00:00:41,900 --> 00:00:43,900
and only the egg whites should be used.

12
00:00:44,300 --> 00:00:48,400
But that's not necessarily true. They might assume something else. See that's the problem.

13
00:00:48,400 --> 00:00:52,400
A computer would probably put the eggs, shells and all into a bowl and mix them.

14
00:00:52,800 --> 00:00:56,800
So when we write programs, we need to be very, very explicit about

15
00:00:56,800 --> 00:00:58,400
what we want the computer to do.

16
00:00:58,700 --> 00:01:01,500
Otherwise, our result will probably be incorrect.

17
00:01:03,000 --> 00:01:06,000
In order to write programs, we use programming languages.

18
00:01:06,000 --> 00:01:08,460
There are many, many programming languages out there.

19
00:01:08,460 --> 00:01:10,460
In this class, we'll be using C++.

20
00:01:11,060 --> 00:01:13,360
The code we write is called source code.

21
00:01:13,660 --> 00:01:16,960
Source code is generally higher level than computer code

22
00:01:16,960 --> 00:01:19,260
since it needs to be understandable by humans,

23
00:01:19,460 --> 00:01:22,860
and humans aren't very good at reading long streams of zeros and ones.

24
00:01:24,360 --> 00:01:27,360
We write our programs using programming editors.

25
00:01:27,360 --> 00:01:31,560
These editors are like word processors, specifically designed to write

26
00:01:31,560 --> 00:01:34,560
these recipes in a specific programming language.

27
00:01:35,860 --> 00:01:39,760
C++ programs have an extension like .cpp .h .cc

28
00:01:39,760 --> 00:01:43,760
hpp and there are several others.

29
00:01:44,160 --> 00:01:46,960
In this course, we will use .cpp

30
00:01:46,960 --> 00:01:49,960
and .h as the extensions for the code we write.

31
00:01:50,960 --> 00:01:54,060
Just as humans aren't very good at reading computer code,

32
00:01:54,060 --> 00:01:56,560
computers aren't very good at reading source code.

33
00:01:56,560 --> 00:02:01,160
We need to translate the source code to a form that's understandable by the computer.

34
00:02:01,710 --> 00:02:05,810
This form is called object code, and the compiler is the translator.

35
00:02:07,010 --> 00:02:10,570
The c++ compiler is a program that takes as input

36
00:02:10,570 --> 00:02:14,770
C++ source code and produces object code as output.

37
00:02:15,370 --> 00:02:19,170
If the source code has errors, then no object code is produced.

38
00:02:20,770 --> 00:02:24,130
Since our code might depend on code that other programmers wrote,

39
00:02:24,630 --> 00:02:28,830
this is actually a very likely scenario because we want to reuse as much existing code

40
00:02:28,830 --> 00:02:30,130
that's out there as possible.

41
00:02:30,330 --> 00:02:32,530
This makes it easier for us to solve our problems.

42
00:02:33,190 --> 00:02:37,290
So a program called the linker takes our object code

43
00:02:37,290 --> 00:02:40,790
and the object code that exists out there in the form of libraries

44
00:02:40,790 --> 00:02:44,090
and links it all together to form an executable program.

45
00:02:44,750 --> 00:02:49,150
That is a program that we can now run that follows the recipe we told the computer

46
00:02:49,150 --> 00:02:50,650
to do using C++.

47
00:02:52,450 --> 00:02:57,350
Now that our program is complete, we test it to find as many errors as possible,

48
00:02:57,350 --> 00:02:59,850
and we debug it to eliminate those errors.

49
00:03:00,250 --> 00:03:03,050
As you can see, there's a lot going on and understanding

50
00:03:03,050 --> 00:03:05,050
what's going on at this high level is important.

51
00:03:06,050 --> 00:03:08,930
The integrated development environments are programs

52
00:03:08,930 --> 00:03:12,830
that allow you to do everything I just mentioned from a common interface.

53
00:03:12,830 --> 00:03:16,930
Sometimes they make the process seem like magic since all you need to do is click a button

54
00:03:16,930 --> 00:03:18,930
and the entire build process happens.

55
00:03:19,290 --> 00:03:22,290
Let's go over this build process one more time in a visual manner.

56
00:03:23,790 --> 00:03:27,840
First, we use an editor to enter our C++ code or to edit

57
00:03:27,840 --> 00:03:29,440
existing C++ code.

58
00:03:30,240 --> 00:03:33,240
Note that we can have many C++ source files.

59
00:03:33,240 --> 00:03:36,840
In this course, we'll be using a single main.cpp file

60
00:03:36,840 --> 00:03:38,440
until our programs get larger.

61
00:03:39,100 --> 00:03:43,200
Then we'll need several C++ source files to better organize our program.

62
00:03:43,200 --> 00:03:47,600
Production C++ programs can have hundreds and even thousands of source files

63
00:03:47,600 --> 00:03:49,100
and millions of lines of code.

64
00:03:50,500 --> 00:03:54,700
Then we need to compile the C++ code using a C++ compiler.

65
00:03:55,300 --> 00:03:58,500
If the code contains no syntax errors,

66
00:03:58,500 --> 00:04:01,600
then the compiler will generate an object code file

67
00:04:01,600 --> 00:04:03,600
for each C++ source file.

68
00:04:05,000 --> 00:04:08,800
On windows, the object files have .obj extensions,

69
00:04:08,800 --> 00:04:11,800
and on UNIX and mac they will have .o extensions.

70
00:04:12,750 --> 00:04:16,550
Finally, the object files and any libraries that our program

71
00:04:16,550 --> 00:04:18,550
requires must be linked together.

72
00:04:19,750 --> 00:04:23,250
This final step creates an executable file that can run.

73
00:04:23,750 --> 00:04:26,950
On windows, the file extension will be .exe.

74
00:04:26,950 --> 00:04:29,950
And on UNIX and mac, they typically don't have any extensions.

75
00:04:30,450 --> 00:04:32,150
But remember, we're not done yet.

76
00:04:32,150 --> 00:04:35,050
You must test your program to find any logic errors

77
00:04:35,050 --> 00:04:37,050
and debug it to eliminate those errors.

78
00:04:37,850 --> 00:04:41,850
Let's wrap up this video by looking at some of the available IDEs that can help us

79
00:04:41,850 --> 00:04:42,750
with this process.

80
00:04:44,750 --> 00:04:46,310
As mentioned previously,

81
00:04:46,310 --> 00:04:50,770
IDEs are programs that provide an editor a way to compile,

82
00:04:50,770 --> 00:04:52,570
link and execute your source code.

83
00:04:53,370 --> 00:04:57,870
They also often have debuggers that can help you understand your code and fix errors.

84
00:04:58,370 --> 00:05:02,070
Most beginning C++ courses don't cover integrated debuggers at all.

85
00:05:02,370 --> 00:05:05,070
I think this is a mistake and I plan to cover the debugger

86
00:05:05,070 --> 00:05:08,070
once we have the basics of C++ behind us.

87
00:05:08,470 --> 00:05:11,800
IDEs also help us keep our files in sync

88
00:05:11,800 --> 00:05:16,000
and provide hooks to version control systems such as git and subversion.

89
00:05:17,200 --> 00:05:21,300
There are many IDEs available. I've used all the ones listed here and others.

90
00:05:21,300 --> 00:05:24,600
The selection of an IDE for this course was not an easy one.

91
00:05:25,000 --> 00:05:27,300
I wanted an IDE that was free,

92
00:05:27,300 --> 00:05:31,290
cross-platform and had a relatively small hardware requirement to run.

93
00:05:31,790 --> 00:05:35,890
In this course, we'll use CodeLight as the IDE since it meets all of these criteria.

94
00:05:36,390 --> 00:05:38,390
However, there is no perfect IDE.

95
00:05:38,890 --> 00:05:41,190
As a professional developer many times you use

96
00:05:41,190 --> 00:05:43,790
whatever ide is used by the team you're working with,

97
00:05:44,390 --> 00:05:48,990
as a consultant you should learn as many IDEs as you can and always have an editor

98
00:05:48,990 --> 00:05:50,890
command line preference available as well.

99
00:05:51,690 --> 00:05:55,390
As you gain experience in C++, I encourage you to experiment with the various

100
00:05:55,390 --> 00:05:57,890
IDEs and find one that works for you.

101
00:05:58,390 --> 00:06:00,690
Let me talk briefly about the ones that are listed here.

102
00:06:01,190 --> 00:06:04,690
CodeLight, as I mentioned, is the IDE that we're going to use in this course.

103
00:06:04,690 --> 00:06:09,290
It's free. It's cross-platform. It's fast and the memory requirements are minimal.

104
00:06:10,090 --> 00:06:13,590
Code Blocks is also a nice cross-platform IDE.

105
00:06:13,590 --> 00:06:17,890
However, the mac version is pretty buggy and it kept crashing on me all the time.

106
00:06:19,090 --> 00:06:21,590
NetBeans is the oracle IDE.

107
00:06:22,250 --> 00:06:24,910
It's used mainly to develop java code,

108
00:06:24,910 --> 00:06:28,810
but they've got a plug-in for C++. It's actually very good.

109
00:06:28,810 --> 00:06:31,310
It's a great cross-platform IDE.

110
00:06:31,310 --> 00:06:35,310
The problem is that it requires Java jre install and the memory requirements

111
00:06:35,310 --> 00:06:36,510
can be pretty significant.

112
00:06:37,760 --> 00:06:40,460
Same thing with Eclipse it supports many different languages.

113
00:06:40,460 --> 00:06:43,460
It's cross-platform but it's got pretty good memory requirements.

114
00:06:44,120 --> 00:06:46,820
CLion is an IDE by JetBrains.

115
00:06:46,820 --> 00:06:50,620
This is the company that's created Kotlin, intellij, android studio.

116
00:06:51,020 --> 00:06:54,620
This is an awesome IDE. This is my ide of choice,

117
00:06:54,770 --> 00:06:57,370
but it's not free, it's actually quite expensive.

118
00:06:58,170 --> 00:07:02,270
But there's a download available that gives you a 30-day trial. You can try it out and see if you like it.

119
00:07:02,930 --> 00:07:07,130
Dev-C++ is a CC++ windows only environment.

120
00:07:07,130 --> 00:07:11,030
It's small. It's fast and it's a nice IDE but again it's windows only.

121
00:07:11,580 --> 00:07:14,880
KDevelop is a cross-platform, multiple-language IDE.

122
00:07:15,380 --> 00:07:17,880
However, there is no mac binary available.

123
00:07:17,880 --> 00:07:20,480
If you want to use it on mac, you have to build it from the source.

124
00:07:21,780 --> 00:07:26,280
Finally, visual studio and XCode are Microsoft

125
00:07:26,280 --> 00:07:28,980
and apple's development environments respectively.

126
00:07:28,980 --> 00:07:31,580
Visual studio is a great development environment.

127
00:07:31,580 --> 00:07:34,570
It runs on windows only in the C++ version.

128
00:07:34,570 --> 00:07:38,570
They have a mac version of visual studio now but it doesn't support C++.

129
00:07:39,170 --> 00:07:41,770
And XCode is mac only.

130
00:07:41,770 --> 00:07:45,370
Again it's a great development environment. If you're a mac developer,

131
00:07:45,370 --> 00:07:49,170
you're probably already using it for iOS development, mac OS 10 development,

132
00:07:49,170 --> 00:07:50,670
swift development and so forth.

133
00:07:51,170 --> 00:07:55,370
But as I mentioned, it's mac only but it's a great development environment.

134
00:07:55,370 --> 00:07:57,570
There are many more IDEs available.

135
00:07:57,570 --> 00:08:00,570
If you find one you like and you think others in the course should know about it,

136
00:08:00,570 --> 00:08:03,570
please post that information about the IDE in the course forum.

137
00:08:04,230 --> 00:08:06,330
Well, that wraps up this video. I hope you now have a

138
00:08:06,330 --> 00:08:09,630
better understanding of the build process in C++

139
00:08:09,630 --> 00:08:12,630
and how IDEs can help make programmers more productive.