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| -rw-r--r-- | Readme.adoc | 93 | ||||
| -rw-r--r-- | tips/formatting.adoc | 104 |
2 files changed, 108 insertions, 89 deletions
diff --git a/Readme.adoc b/Readme.adoc index 469b93b..8152ee6 100644 --- a/Readme.adoc +++ b/Readme.adoc @@ -22,96 +22,11 @@ image::img/ss_20220916_200135.png[Debugging is essential] === Formatting -In my opinion, using +Using https://cplusplus.com/reference/library/manipulators/[ stream manipulators] and https://cplusplus.com/reference/ios/ios_base/fmtflags/[ -stream format flags] is cumbersome, but the course _requires_ it’s use (using -`printf` is not allowed). So maybe the following macro eases it’s use. +stream format flags] can be cumbersome, but the course _requires_ them since +using `printf` is not allowed. So maybe macros can be helpful here. -[source,c++] ----- -// [aux.h] - -/* Stream manipulator macros - * ========================= - * - * Requires <iostream> and <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 << setprecision(2) << fixed - -// 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-Date (dd/mm/yyyy format) -#define WD(w, x) setw((w) - 10) << "" << WR0(2, 2, (x) % 100) \ - << '/' << WR0(2, 2, (x) / 100 % 100) \ - << '/' << WR0(4, 4, (x) / 10000) ----- - -Example usage: - -[source, c++] ----- -//[example.cpp] -#include <iostream> -#include <iomanip> -#include "aux.h" // easier to import a single .h to any .cpp -#define MAXLEN 100 -using namespace std; -typedef struct { - int id; - const char name[MAXLEN]; - double luckynumber; - int dob; // date of birth -} student_t; -// dd/mm/yyyy -void printdate(ostream &os, int date) { - int d = date % 100; - int mo = date / 100 % 100; - int y = date / 10000; - os << " " << WR0(2, 2, d) - << '/' << WR0(2, 2, mo) - << '/' << WR0(4, 4, y); -} -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 << WD(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 ----- - -NOTE: Macros are useful, but don't abuse them. They are hard to debug. +See link:tips/formatting.adoc[] for an example implementation and usage. diff --git a/tips/formatting.adoc b/tips/formatting.adoc new file mode 100644 index 0000000..3180aeb --- /dev/null +++ b/tips/formatting.adoc @@ -0,0 +1,104 @@ +: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 + * ========================= + * + * Requires <iostream> and <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 << setprecision(2) << fixed + +// 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) + +#define MAXLEN 100 +---- + +Example usage: + +[source, c++] +---- +//[example.cpp] + +/* Example usage + * ============= */ + +#include <iostream> +#include <iomanip> +#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 +---- |