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Diffstat (limited to 'content/html/gemfeed/2016-11-20-methods-in-c.html')
| -rw-r--r-- | content/html/gemfeed/2016-11-20-methods-in-c.html | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/content/html/gemfeed/2016-11-20-methods-in-c.html b/content/html/gemfeed/2016-11-20-methods-in-c.html index 2bf02ed1..3b2efa46 100644 --- a/content/html/gemfeed/2016-11-20-methods-in-c.html +++ b/content/html/gemfeed/2016-11-20-methods-in-c.html @@ -25,7 +25,7 @@ li { color: #98be65; } <h2>Example</h2> <p>Lets have a look at the following sample program. Basically all you have to do is to add a function pointer such as "calculate" to the definition of struct "something_s". Later, during the struct initialization, assign a function address to that function pointer:</p> <pre> -#include <stdio.h> +#include <lt;stdio.h>gt; typedef struct { double (*calculate)(const double, const double); @@ -53,26 +53,26 @@ int main(void) { const double a = 3, b = 2; - printf("%s(%f, %f) => %f\n", mult.name, a, b, mult.calculate(a,b)); - printf("%s(%f, %f) => %f\n", div.name, a, b, div.calculate(a,b)); + printf("%s(%f, %f) =>gt; %f\n", mult.name, a, b, mult.calculate(a,b)); + printf("%s(%f, %f) =>gt; %f\n", div.name, a, b, div.calculate(a,b)); } </pre> <p>As you can see you can call the function (pointed by the function pointer) the same way as in C++ or Java via:</p> <pre> -printf("%s(%f, %f) => %f\n", mult.name, a, b, mult.calculate(a,b)); -printf("%s(%f, %f) => %f\n", div.name, a, b, div.calculate(a,b)); +printf("%s(%f, %f) =>gt; %f\n", mult.name, a, b, mult.calculate(a,b)); +printf("%s(%f, %f) =>gt; %f\n", div.name, a, b, div.calculate(a,b)); </pre> <p>However, that's just syntactic sugar for:</p> <pre> -printf("%s(%f, %f) => %f\n", mult.name, a, b, (*mult.calculate)(a,b)); -printf("%s(%f, %f) => %f\n", div.name, a, b, (*div.calculate)(a,b)); +printf("%s(%f, %f) =>gt; %f\n", mult.name, a, b, (*mult.calculate)(a,b)); +printf("%s(%f, %f) =>gt; %f\n", div.name, a, b, (*div.calculate)(a,b)); </pre> <p>Output:</p> <pre> pbuetow ~/git/blog/source [38268]% gcc methods-in-c.c -o methods-in-c pbuetow ~/git/blog/source [38269]% ./methods-in-c -Multiplication(3.000000, 2.000000) => 6.000000 -Division(3.000000, 2.000000) => 1.500000 +Multiplication(3.000000, 2.000000) =>gt; 6.000000 +Division(3.000000, 2.000000) =>gt; 1.500000 </pre> <p>Not complicated at all, but nice to know and helps to make the code easier to read!</p> <h2>Taking it further</h2> |