1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
:source-highlighter: highlight.js
To print tabulated fields in plain text I first divide the desired ouput by the
number of columns each field should take. For example:
----
dni name birdthdate
12345678 Ana Allen 12/10/1998
<- 12 col -><------ 24 col --------><- 12 col ->
----
I like to use multiples of 4, but multiples of 8 or 10 are good options too.
The nice thing about 4 is that it aligns with my text editor's default tabstop
setting. It helps when writting report headers.
NOTE: Left-aligned fields after a right-aligned field need a space in
between. I like to just add the space to all left-aligned fields.
WARNING: Macros are useful, but don't abuse them. They are hard to debug.
Example implementation:
[source,c++]
----
//[aux.h]
/* Stream manipulator macros
* =========================
*/
#include <iostream>
#include <iomanip>
// The parenthesis in C/C++ macros are best practice
// https://stackoverflow.com/q/7186504/7498073
// Width-Left (use with strings)
#define WL(w) " " << setw((w) - 1) << left
// Width-Right (use with numbers)
#define WR(w) setw(w) << right << setprecision(2) << fixed
// Width-Right-0-padding
#define WR0(w, w0, x) setw((w) - (w0)) << "" \
<< setw(w0) << right << setfill('0') \
<< setprecision(2) << fixed << (x) \
<< setfill(' ')
// Width-Left-Date (dd/mm/yyyy format)
#define WLD(w, x) setw((w) - 10) << "" << WR0(2, 2, (x) % 100) \
<< '/' << WR0(2, 2, (x) / 100 % 100) \
<< '/' << WR0(4, 4, (x) / 10000)
// (for character arrays)
#define MAXLEN 100
// (for static arrays of items)
#define MAXITEMS 1000
----
Example usage:
[source, c++]
----
//[example.cpp]
/* Example usage
* ============= */
#include "aux.h" // It's easier to import a single .h to many .cpp files
using namespace std;
typedef struct {
int id;
const char name[MAXLEN];
double luckynumber;
int dob; // date of birth
} student_t;
int main(int argc, char *argv[])
{
student_t students[] = {
{1, "Ana Ambooken", 69.420, 19990606},
{2, "Bob Banana", 666.66, 19760411},
{3, "Carlos Clear", 123.456, 20000101}
};
int n = 3;
for (int i = 0; i < n; i++) {
cout << WR0(8, 4, students[i].id)
<< WL(40) << students[i].name
<< WR(8) << students[i].luckynumber;
cout << WLD(12, students[i].dob);
cout << '\n';
}
return 0;
}
----
Output:
----
0001 Ana Ambooken 69.42 06/06/1999
0002 Bob Banana 666.66 11/04/1976
0003 Carlos Clear 123.46 01/01/2000
----
|
