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
|
//This module defines the domain specific language.
use std::{rc::Rc, borrow::Cow};
use higher_free_macro::free;
use std::convert::identity;
use higher::Functor;
use super::data::{Location, Mood, Speaker};
#[derive(Clone)]
pub enum SausageRoll<'a, 's,A>{
SayDialogueLine{
speaker: Speaker,
text : Cow<'s, str>, //In a real project I would just make this a String. Here it's a reference to show off lifetime support.
mood : Mood,
next : A
},
GivePlayerOptions{
options : Vec<&'s str>,
next : Rc<dyn Fn(usize)-> A + 'a> //let's just assume that the interpreter validates input.
},
PresentLocation{
location : Location,
next : A,
},
Exposition{
text : &'s str,
next : A,
}
}
impl<'a,'s, A : 'a> Functor<'a,A> for SausageRoll<'a,'s,A>{
type Target<T> = SausageRoll<'a,'s,T>;
fn fmap<B, F>(self, f: F) -> Self::Target<B>
where
F: Fn(A) -> B + 'a {
match self {
SausageRoll::SayDialogueLine { speaker, text, mood, next } => SausageRoll::SayDialogueLine { speaker, text, mood, next: f(next) },
SausageRoll::GivePlayerOptions { options, next } => SausageRoll::GivePlayerOptions { options, next: Rc::new(move |x| f(next(x))) },
SausageRoll::PresentLocation { location, next } => SausageRoll::PresentLocation { location, next: f(next) },
SausageRoll::Exposition { text, next } => SausageRoll::Exposition { text, next: f(next) },
}
}
}
free!(<'a>, pub FreeSausageRoll<'a,'s,A>, SausageRoll<'a, 's, FreeSausageRoll<'a,'s,A>>);
pub fn say_dialogue_line<'a,'s:'a>(speaker : Speaker, text : Cow<'s,str>, mood : Mood) -> FreeSausageRoll<'a, 's, ()>{
FreeSausageRoll::lift_f(SausageRoll::SayDialogueLine { speaker, text, mood, next: () })
}
pub fn give_player_options<'a,'s:'a>(options : Vec<&'s str>) -> FreeSausageRoll<'a,'s, usize>{
FreeSausageRoll::lift_f(SausageRoll::GivePlayerOptions { options, next: Rc::new(identity) })
}
pub fn present_location<'a, 's:'a>(location : Location) -> FreeSausageRoll<'a,'s, ()>{
FreeSausageRoll::lift_f(SausageRoll::PresentLocation { location, next: () })
}
pub fn exposition<'a,'s:'a>(text : &'s str) -> FreeSausageRoll<'a,'s,()>{
FreeSausageRoll::lift_f(SausageRoll::Exposition { text, next: () })
}
|
