Re: Builder: Tiny Utility Library to Add a Builder API to Classes
On Friday, 6 January 2023 at 12:54:07 UTC, Vijay Nayar wrote:
On Friday, 6 January 2023 at 09:26:51 UTC, thebluepandabear
wrote:
.isActive(true)
.build();
```
Good
how would I extend the builder methods?
The builder methods are automatically generated and go up the
inheritance chain to capture all the fields in your class. (I
assume that you are referring to inheritance when you say
"extend"?)
Here is one of the unit-tests demonstrating this:
```
class A2 {
int a;
string b;
}
class B2 : A2 {
int c;
mixin AddBuilder!(typeof(this));
}
/// All inherited fields should be available from the builder.
unittest {
B2 b2 = B2.builder()
.a(3)
.b("ham")
.c(4)
.build();
assert(b2.a == 3);
assert(b2.b == "ham");
assert(b2.c == 4);
}
```
I meant what if I want some extra behavior for the setter method
other than just assigning a value to the field. E.g. if I set a
password field, I might want to validate that it's valid.
Re: Builder: Tiny Utility Library to Add a Builder API to Classes
On Friday, 6 January 2023 at 09:26:51 UTC, thebluepandabear wrote:
.isActive(true)
.build();
```
Good
how would I extend the builder methods?
The builder methods are automatically generated and go up the
inheritance chain to capture all the fields in your class. (I
assume that you are referring to inheritance when you say
"extend"?)
Here is one of the unit-tests demonstrating this:
```
class A2 {
int a;
string b;
}
class B2 : A2 {
int c;
mixin AddBuilder!(typeof(this));
}
/// All inherited fields should be available from the builder.
unittest {
B2 b2 = B2.builder()
.a(3)
.b("ham")
.c(4)
.build();
assert(b2.a == 3);
assert(b2.b == "ham");
assert(b2.c == 4);
}
```
Re: Builder: Tiny Utility Library to Add a Builder API to Classes
.isActive(true) .build(); ``` Good how would I extend the builder methods?
Re: Builder: Tiny Utility Library to Add a Builder API to Classes
On Thursday, 5 January 2023 at 23:31:36 UTC, Vladimir Marchevsky
wrote:
On Thursday, 5 January 2023 at 21:48:40 UTC, Vijay Nayar wrote:
2. Using a constructor with many arguments.
```
A a = new A("Bob", 20, false, true);
```
This approach can construct arguments inline, such as during a
function call, however, the arguments are not labeled, making
it easy to get the order wrong or for the meaning to be
unclear.
Hopefully we'll finally have named arguments. Considering they
were accepted to language more than two years ago - maybe in
the next century...
Named arguments would definitely obviate this tool, but in the
meanwhile, this tool basically lets you achieve the same
objectives in terms of single-expression construction and clearly
labeled arguments. I guess one extra advantage of the `builder`
library is that you also don't have to bother writing a
constructor at all and can just use the default one.
Re: Builder: Tiny Utility Library to Add a Builder API to Classes
On Thursday, 5 January 2023 at 21:48:40 UTC, Vijay Nayar wrote:
2. Using a constructor with many arguments.
```
A a = new A("Bob", 20, false, true);
```
This approach can construct arguments inline, such as during a
function call, however, the arguments are not labeled, making
it easy to get the order wrong or for the meaning to be unclear.
Hopefully we'll finally have named arguments. Considering they
were accepted to language more than two years ago - maybe in the
next century...
