maflow/
lib.rs

1pub trait YayNay {
2    fn yay(&self) -> bool;
3    fn nay(&self) -> bool;
4}
5impl YayNay for bool {
6    fn yay(&self) -> bool {*self}
7    fn nay(&self) -> bool {!*self}
8}
9impl <A> YayNay for Option<A>{
10    fn yay(&self) -> bool {self.is_some()}
11    fn nay(&self) -> bool {self.is_none()}
12}
13impl <A,B> YayNay for Result<A,B>{
14    fn yay(&self) -> bool {self.is_ok()}
15    fn nay(&self) -> bool {self.is_err()}
16}
17
18#[macro_export]
19macro_rules! flow_base {
20    ($block:block $($any:tt)*) => {if $($any)* {$block}};
21}
22
23#[macro_export]
24macro_rules! flow_base_let {
25    ($block:block ?$opt:expr) => {
26        if $opt.nay() {$block}
27    };
28    ($block:block *$($opt:tt)*) => {
29        let $($opt)* else {$block};
30    };
31    ($block:block $($var:ident)* =$opt:expr $(,$($plus:tt)*)*) => {
32        let $($var)* = {
33            let _tmp = $opt;
34            if _tmp.nay() {$block}
35            _tmp.unwrap()$(.$($plus)*)*
36        };
37    };
38    ($block:block ($($($var:ident)*),*)=$opt:expr $(,$($plus:tt)*)*) => {
39        let ($($($var)*),*) = {
40            let _tmp = $opt;
41            if _tmp.nay() {$block}
42            _tmp.unwrap()$(.$($plus)*)*
43        };
44    };
45    ($block:block [$($($var:ident)*),*]=$opt:expr $(,$($plus:tt)*)*) => {
46        let [$($($var)*),*] = {
47            let _tmp = $opt;
48            if _tmp.nay() {$block}
49            _tmp.unwrap()$(.$($plus)*)*
50        };
51    };    
52}
53
54#[macro_export]
55macro_rules! exit {
56    () => {return Default::default()};
57    (>if ($($any:tt)*) $($ret:tt)*) => {flow_base!{{return $($ret)*} $($any)*}};
58    (if $($any:tt)*) => {flow_base!{{return Default::default()} $($any)*}};
59    (>($($any:tt)*) $($ret:tt)*) => {flow_base_let!{{return $($ret)*} $($any)*}};
60    ($($any:tt)*) => {flow_base_let!{{return Default::default()} $($any)*}};
61}
62
63#[macro_export]
64macro_rules! next {
65    (if $($any:tt)*) => {flow_base!{{continue} $($any)*}};
66    ($($any:tt)*) => {flow_base_let!{{continue} $($any)*}};
67}
68
69#[macro_export]
70macro_rules! kill {
71    (if $($any:tt)*) => {flow_base!{{panic!()} $($any)*}};
72    ($($any:tt)*) => {flow_base_let!{{panic!()} $($any)*}};
73}
74
75#[macro_export]
76macro_rules! hold {
77    (if $($any:tt)*) => {flow_base!{{break} $($any)*}};
78    ($($any:tt)*) => {flow_base_let!{{break} $($any)*}};
79}
maflow/lib.rs

maflow/
lib.rs
