diff options
-rw-r--r-- | d.html.markdown | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/d.html.markdown b/d.html.markdown index 88a83e41..80c1dc65 100644 --- a/d.html.markdown +++ b/d.html.markdown @@ -74,16 +74,18 @@ are passed to functions by value (i.e. copied) and classes are passed by referen we can use templates to parameterize all of these on both types and values! ```c -// Here, T is a type parameter. Think <T> from C++/C#/Java +// Here, 'T' is a type parameter. Think '<T>' from C++/C#/Java. struct LinkedList(T) { T data = null; - LinkedList!(T)* next; // The ! is used to instaniate a parameterized type. Again, think <T> + + // Use '!' to instantiate a parameterized type. Again, think '<T>'. + LinkedList!(T)* next; } class BinTree(T) { T data = null; - // If there is only one template parameter, we can omit the parentheses + // If there is only one template parameter, we can omit the parentheses. BinTree!T left; BinTree!T right; } @@ -98,13 +100,11 @@ enum Day { Saturday, } -// Use alias to create abbreviations for types - +// Use alias to create abbreviations for types. alias IntList = LinkedList!int; alias NumTree = BinTree!double; // We can create function templates as well! - T max(T)(T a, T b) { if(a < b) return b; @@ -112,9 +112,8 @@ T max(T)(T a, T b) { return a; } -// Use the ref keyword to ensure pass by referece. -// That is, even if a and b are value types, they -// will always be passed by reference to swap +// Use the ref keyword to ensure pass by reference. That is, even if 'a' and 'b' +// are value types, they will always be passed by reference to 'swap()'. void swap(T)(ref T a, ref T b) { auto temp = a; @@ -122,13 +121,13 @@ void swap(T)(ref T a, ref T b) { b = temp; } -// With templates, we can also parameterize on values, not just types +// With templates, we can also parameterize on values, not just types. class Matrix(uint m, uint n, T = int) { T[m] rows; T[n] columns; } -auto mat = new Matrix!(3, 3); // We've defaulted type T to int +auto mat = new Matrix!(3, 3); // We've defaulted type 'T' to 'int'. ``` @@ -138,21 +137,20 @@ have the syntax of POD structures (`structure.x = 7`) with the semantics of getter and setter methods (`object.setX(7)`)! ```c -// Consider a class parameterized on a types T, U - +// Consider a class parameterized on types 'T' & 'U'. class MyClass(T, U) { T _data; U _other; - } -// And "getter" and "setter" methods like so +// And "getter" and "setter" methods like so: class MyClass(T, U) { T _data; U _other; - // Constructors are always named `this` + // Constructors are always named 'this'. this(T t, U u) { + // This will call the setter methods below. data = t; other = u; } @@ -175,16 +173,24 @@ class MyClass(T, U) { _other = u; } } -// And we use them in this manner +// And we use them in this manner: void main() { - auto mc = MyClass!(int, string); + auto mc = new MyClass!(int, string)(7, "seven"); + + // Import the 'stdio' module from the standard library for writing to + // console (imports can be local to a scope). + import std.stdio; + + // Call the getters to fetch the values. + writefln("Earlier: data = %d, str = %s", mc.data, mc.other); - mc.data = 7; - mc.other = "seven"; + // Call the setters to assign new values. + mc.data = 8; + mc.other = "eight"; - writeln(mc.data); - writeln(mc.other); + // Call the getters again to fetch the new values. + writefln("Later: data = %d, str = %s", mc.data, mc.other); } ``` |