From 75362bd2a888621ba8d07a3045f015286fa80857 Mon Sep 17 00:00:00 2001
From: PoiScript <poiscript@gmail.com>
Date: Mon, 14 Jan 2019 14:10:12 +0800
Subject: [PATCH] refactor: utils macros

---
 src/elements/block.rs      |  2 +-
 src/elements/dyn_block.rs  |  2 +-
 src/elements/fn_def.rs     |  2 +-
 src/elements/keyword.rs    |  2 +-
 src/elements/rule.rs       |  2 +-
 src/objects/cookie.rs      |  4 +-
 src/objects/emphasis.rs    |  8 ++--
 src/objects/entity.rs      |  2 +-
 src/objects/fn_ref.rs      |  2 +-
 src/objects/inline_call.rs | 10 ++--
 src/objects/inline_src.rs  |  8 ++--
 src/objects/link.rs        |  4 +-
 src/objects/macros.rs      |  4 +-
 src/objects/snippet.rs     |  2 +-
 src/objects/target.rs      | 12 ++---
 src/utils.rs               | 95 +++++++++++++++-----------------------
 16 files changed, 70 insertions(+), 91 deletions(-)

diff --git a/src/elements/block.rs b/src/elements/block.rs
index a482645..972fbf3 100644
--- a/src/elements/block.rs
+++ b/src/elements/block.rs
@@ -11,7 +11,7 @@ impl Block {
 
         let args = eol!(src);
         let name = until_while!(src, 8, |c| c == b' ' || c == b'\n', |c: u8| c
-            .is_ascii_alphabetic());
+            .is_ascii_alphabetic())?;
         // TODO: ignore case match
         let content = src.find(&format!("\n#+END_{}", &src[8..name]))?;
         let end = eol!(src, content + 1);
diff --git a/src/elements/dyn_block.rs b/src/elements/dyn_block.rs
index 0c9036a..e8ac9b8 100644
--- a/src/elements/dyn_block.rs
+++ b/src/elements/dyn_block.rs
@@ -11,7 +11,7 @@ impl DynBlock {
 
         let args = eol!(src);
         let name = until_while!(src, 9, |c| c == b' ' || c == b'\n', |c: u8| c
-            .is_ascii_alphabetic());
+            .is_ascii_alphabetic())?;
         // TODO: ignore case matching
         let content = src.find("\n#+END:")?;
         let end = eol!(src, content + 1);
diff --git a/src/elements/fn_def.rs b/src/elements/fn_def.rs
index cfa89d2..07c1815 100644
--- a/src/elements/fn_def.rs
+++ b/src/elements/fn_def.rs
@@ -11,7 +11,7 @@ impl FnDef {
     pub fn parse(src: &str) -> Option<(&str, &str, usize)> {
         starts_with!(src, "[fn:");
 
-        let label = until_while!(src, 4, b']', valid_label);
+        let label = until_while!(src, 4, b']', valid_label)?;
 
         if label == 4 {
             return None;
diff --git a/src/elements/keyword.rs b/src/elements/keyword.rs
index 6c1ffa2..1ee9fd6 100644
--- a/src/elements/keyword.rs
+++ b/src/elements/keyword.rs
@@ -9,7 +9,7 @@ impl Keyword {
             starts_with!(src, "#+");
         }
 
-        let key = until_while!(src, 2, b':', |c: u8| c.is_ascii_uppercase() || c == b'_');
+        let key = until_while!(src, 2, b':', |c: u8| c.is_ascii_uppercase() || c == b'_')?;
 
         // includes the eol character
         let end = src.find('\n').map(|i| i + 1).unwrap_or_else(|| src.len());
diff --git a/src/elements/rule.rs b/src/elements/rule.rs
index 27e3b35..287c4bf 100644
--- a/src/elements/rule.rs
+++ b/src/elements/rule.rs
@@ -5,7 +5,7 @@ pub struct Rule;
 impl Rule {
     pub fn parse(src: &str) -> Option<usize> {
         let end = eol!(src);
-        let leading = until_while!(src, 0, b'-', |c| c == b' ' || c == b'\t');
+        let leading = until_while!(src, 0, b'-', |c| c == b' ' || c == b'\t')?;
         if src[leading..end].chars().all(|c| c == '-') && end - leading > 4 {
             Some(end)
         } else {
diff --git a/src/objects/cookie.rs b/src/objects/cookie.rs
index e93298b..4e13c1d 100644
--- a/src/objects/cookie.rs
+++ b/src/objects/cookie.rs
@@ -11,7 +11,7 @@ impl<'a> Cookie<'a> {
         }
 
         let num1 = until_while!(src, 1, |c| c == b'%' || c == b'/', |c: u8| c
-            .is_ascii_digit());
+            .is_ascii_digit())?;
 
         if src.as_bytes()[num1] == b'%' && *src.as_bytes().get(num1 + 1)? == b']' {
             Some((
@@ -21,7 +21,7 @@ impl<'a> Cookie<'a> {
                 num1 + 2,
             ))
         } else {
-            let num2 = until_while!(src, num1 + 1, b']', |c: u8| c.is_ascii_digit());
+            let num2 = until_while!(src, num1 + 1, b']', |c: u8| c.is_ascii_digit())?;
             Some((
                 Cookie {
                     value: &src[0..=num2],
diff --git a/src/objects/emphasis.rs b/src/objects/emphasis.rs
index 7b2d419..7ec452d 100644
--- a/src/objects/emphasis.rs
+++ b/src/objects/emphasis.rs
@@ -3,7 +3,7 @@ pub struct Emphasis;
 impl Emphasis {
     // TODO: return usize instead of Option<usize>
     pub fn parse(src: &str, marker: u8) -> Option<usize> {
-        expect!(src, 1, |c: u8| !c.is_ascii_whitespace());
+        expect!(src, 1, |c: u8| !c.is_ascii_whitespace())?;
 
         let mut lines = 0;
         let end = until_while!(src, 1, marker, |c| {
@@ -11,9 +11,9 @@ impl Emphasis {
                 lines += 1;
             }
             lines < 2
-        });
+        })?;
 
-        expect!(src, end - 1, |c: u8| !c.is_ascii_whitespace());
+        expect!(src, end - 1, |c: u8| !c.is_ascii_whitespace())?;
 
         if end < src.len() - 1 {
             expect!(src, end + 1, |ch| ch == b' '
@@ -26,7 +26,7 @@ impl Emphasis {
                 || ch == b'\''
                 || ch == b'\n'
                 || ch == b')'
-                || ch == b'}');
+                || ch == b'}')?;
         }
 
         Some(end)
diff --git a/src/objects/entity.rs b/src/objects/entity.rs
index 1358bda..a4d20c5 100644
--- a/src/objects/entity.rs
+++ b/src/objects/entity.rs
@@ -7,7 +7,7 @@ impl<'a> Entity<'a> {
     pub fn parse(src: &'a str) -> Option<(Entity<'a>, usize)> {
         expect!(src, 0, b'\\')?;
 
-        let name = position!(src, 1, |c| !c.is_ascii_alphabetic());
+        let name = 0;
 
         if src.as_bytes()[name] == b'[' {
             Some((
diff --git a/src/objects/fn_ref.rs b/src/objects/fn_ref.rs
index e4a502a..36e3931 100644
--- a/src/objects/fn_ref.rs
+++ b/src/objects/fn_ref.rs
@@ -13,7 +13,7 @@ impl<'a> FnRef<'a> {
     pub fn parse(src: &'a str) -> Option<(FnRef<'a>, usize)> {
         starts_with!(src, "[fn:");
 
-        let label = until_while!(src, 4, |c| c == b']' || c == b':', valid_label);
+        let label = until_while!(src, 4, |c| c == b']' || c == b':', valid_label)?;
 
         if src.as_bytes()[label] == b':' {
             let mut pairs = 1;
diff --git a/src/objects/inline_call.rs b/src/objects/inline_call.rs
index efe8d1b..aa92318 100644
--- a/src/objects/inline_call.rs
+++ b/src/objects/inline_call.rs
@@ -14,28 +14,28 @@ impl<'a> InlineCall<'a> {
         starts_with!(src, "call_");
 
         let mut pos = until_while!(src, 5, |c| c == b'[' || c == b'(', |c: u8| c
-            .is_ascii_graphic());
+            .is_ascii_graphic())?;
         let mut pos_;
 
         let name = &src[5..pos];
 
         let inside_header = if src.as_bytes()[pos] == b'[' {
             pos_ = pos;
-            pos = until_while!(src, pos, b']', |c: u8| c != b'\n') + 1;
-            expect!(src, pos, b'(');
+            pos = until_while!(src, pos, b']', |c: u8| c != b'\n')? + 1;
+            expect!(src, pos, b'(')?;
             Some(&src[pos_ + 1..pos - 1])
         } else {
             None
         };
 
         pos_ = pos;
-        pos = until_while!(src, pos, b')', |c| c != b'\n');
+        pos = until_while!(src, pos, b')', |c| c != b'\n')?;
         let args = &src[pos_ + 1..pos];
 
         let end_header = if src.len() > pos + 1 && src.as_bytes()[pos + 1] == b'[' {
             pos_ = pos;
             pos = until_while!(src, pos_ + 1, |c| c == b']', |c: u8| c != b'\n'
-                && c != b')');
+                && c != b')')?;
             Some(&src[pos_ + 2..pos])
         } else {
             None
diff --git a/src/objects/inline_src.rs b/src/objects/inline_src.rs
index c4b2c3c..5482b39 100644
--- a/src/objects/inline_src.rs
+++ b/src/objects/inline_src.rs
@@ -11,15 +11,15 @@ impl<'a> InlineSrc<'a> {
         starts_with!(src, "src_");
 
         let lang = until_while!(src, 4, |c| c == b'[' || c == b'{', |c: u8| !c
-            .is_ascii_whitespace());
+            .is_ascii_whitespace())?;
 
         if lang == 4 {
             return None;
         }
 
         if src.as_bytes()[lang] == b'[' {
-            let option = until_while!(src, lang, b']', |c| c != b'\n');
-            let body = until_while!(src, option, b'}', |c| c != b'\n');
+            let option = until_while!(src, lang, b']', |c| c != b'\n')?;
+            let body = until_while!(src, option, b'}', |c| c != b'\n')?;
 
             Some((
                 InlineSrc {
@@ -30,7 +30,7 @@ impl<'a> InlineSrc<'a> {
                 body + 1,
             ))
         } else {
-            let body = until_while!(src, lang, b'}', |c| c != b'\n');
+            let body = until_while!(src, lang, b'}', |c| c != b'\n')?;
 
             Some((
                 InlineSrc {
diff --git a/src/objects/link.rs b/src/objects/link.rs
index 10473ee..e9600f2 100644
--- a/src/objects/link.rs
+++ b/src/objects/link.rs
@@ -11,7 +11,7 @@ impl<'a> Link<'a> {
             starts_with!(src, "[[");
         }
 
-        let path = until_while!(src, 2, b']', |c| c != b'<' && c != b'>' && c != b'\n');
+        let path = until_while!(src, 2, b']', |c| c != b'<' && c != b'>' && c != b'\n')?;
 
         if cond_eq!(src, path + 1, b']') {
             Some((
@@ -22,7 +22,7 @@ impl<'a> Link<'a> {
                 path + 2,
             ))
         } else if src.as_bytes()[path + 1] == b'[' {
-            let desc = until_while!(src, path + 2, b']', |c| c != b'[');
+            let desc = until_while!(src, path + 2, b']', |c| c != b'[')?;
             expect!(src, desc + 1, b']')?;
 
             Some((
diff --git a/src/objects/macros.rs b/src/objects/macros.rs
index 0d97b88..ffc22ef 100644
--- a/src/objects/macros.rs
+++ b/src/objects/macros.rs
@@ -15,9 +15,9 @@ impl<'a> Macros<'a> {
     pub fn parse(src: &'a str) -> Option<(Macros<'a>, usize)> {
         starts_with!(src, "{{{");
 
-        expect!(src, 3, |c: u8| c.is_ascii_alphabetic());
+        expect!(src, 3, |c: u8| c.is_ascii_alphabetic())?;
 
-        let name = until_while!(src, 3, |c| c == b'}' || c == b'(', valid_name);
+        let name = until_while!(src, 3, |c| c == b'}' || c == b'(', valid_name)?;
 
         if src.as_bytes()[name] == b'}' {
             expect!(src, name + 1, b'}')?;
diff --git a/src/objects/snippet.rs b/src/objects/snippet.rs
index 51f4316..0c2ddc4 100644
--- a/src/objects/snippet.rs
+++ b/src/objects/snippet.rs
@@ -13,7 +13,7 @@ impl<'a> Snippet<'a> {
             starts_with!(src, "@@");
         }
 
-        let name = until_while!(src, 2, b':', |c: u8| c.is_ascii_alphanumeric() || c == b'-');
+        let name = until_while!(src, 2, b':', |c: u8| c.is_ascii_alphanumeric() || c == b'-')?;
 
         if name == 2 {
             return None;
diff --git a/src/objects/target.rs b/src/objects/target.rs
index dfc5e8b..e5ca8ec 100644
--- a/src/objects/target.rs
+++ b/src/objects/target.rs
@@ -9,11 +9,11 @@ impl<'a> RadioTarget<'a> {
             starts_with!(src, "<<<");
         }
 
-        expect!(src, 3, |c| c != b' ');
+        expect!(src, 3, |c| c != b' ')?;
 
-        let end = until_while!(src, 3, b'>', |c| c != b'<' && c != b'\n');
+        let end = until_while!(src, 3, b'>', |c| c != b'<' && c != b'\n')?;
 
-        expect!(src, end - 1, |c| c != b' ');
+        expect!(src, end - 1, |c| c != b' ')?;
         expect!(src, end + 1, b'>')?;
         expect!(src, end + 2, b'>')?;
 
@@ -31,11 +31,11 @@ impl<'a> Target<'a> {
             starts_with!(src, "<<");
         }
 
-        expect!(src, 2, |c| c != b' ');
+        expect!(src, 2, |c| c != b' ')?;
 
-        let end = until_while!(src, 2, b'>', |c| c != b'<' && c != b'\n');
+        let end = until_while!(src, 2, b'>', |c| c != b'<' && c != b'\n')?;
 
-        expect!(src, end - 1, |c| c != b' ');
+        expect!(src, end - 1, |c| c != b' ')?;
         expect!(src, end + 1, b'>')?;
 
         Some((Target(&src[2..end]), end + 2))
diff --git a/src/utils.rs b/src/utils.rs
index 826e157..c6fc278 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -3,13 +3,10 @@
 #[macro_export]
 macro_rules! expect {
     ($src:ident, $index:expr, $expect:tt) => {
-        $src.as_bytes().get($index).filter(|&b| b == &$expect)
+        $src.as_bytes().get($index).filter(|&&b| b == $expect)
     };
     ($src:ident, $index:expr, $expect:expr) => {
-        // $src.as_bytes().get($index).filter($expect)
-        if $index >= $src.len() || !$expect($src.as_bytes()[$index]) {
-            return None;
-        }
+        $src.as_bytes().get($index).filter(|&&b| $expect(b))
     };
 }
 
@@ -30,30 +27,30 @@ macro_rules! eol {
 macro_rules! until {
     ($src:expr, $until:tt) => {{
         let mut pos = 0;
-        while pos < $src.len() {
-            if $until == $src.as_bytes()[pos] {
-                break;
+        loop {
+            if pos >= $src.len() {
+                break None;
+            }
+
+            if $until == $src.as_bytes()[pos] {
+                break Some(pos);
+            } else {
+                pos += 1;
             }
-            pos += 1;
-        }
-        if pos == $src.len() {
-            None
-        } else {
-            Some(pos)
         }
     }};
     ($src:expr, $until:expr) => {{
         let mut pos = 0;
-        while pos < $src.len() {
-            if $until($src.as_bytes()[pos]) {
-                break;
+        loop {
+            if pos >= $src.len() {
+                break None;
+            }
+
+            if $until($src.as_bytes()[pos]) {
+                break Some(pos);
+            } else {
+                pos += 1;
             }
-            pos += 1;
-        }
-        if pos == $src.len() {
-            None
-        } else {
-            Some(pos)
         }
     }};
 }
@@ -62,41 +59,33 @@ macro_rules! until {
 macro_rules! until_while {
     ($src:expr, $start:expr, $until:tt, $while:expr) => {{
         let mut pos = $start;
-        while pos < $src.len() {
-            // println!("pos {} char {} ", pos, $src.as_bytes()[pos] as char,);
-            if $until == $src.as_bytes()[pos] {
-                break;
+        loop {
+            if pos >= $src.len() {
+                break None;
+            } else if $until == $src.as_bytes()[pos] {
+                break Some(pos);
             } else if $while($src.as_bytes()[pos]) {
                 pos += 1;
                 continue;
             } else {
-                return None;
+                break None;
             }
         }
-        if pos == $src.len() {
-            return None;
-        } else {
-            pos
-        }
     }};
     ($src:expr, $start:expr, $until:expr, $while:expr) => {{
         let mut pos = $start;
-        while pos < $src.len() {
-            // println!("pos {} char {}", pos, $src.as_bytes()[pos] as char);
-            if $until($src.as_bytes()[pos]) {
-                break;
+        loop {
+            if pos >= $src.len() {
+                break None;
+            } else if $until($src.as_bytes()[pos]) {
+                break Some(pos);
             } else if $while($src.as_bytes()[pos]) {
                 pos += 1;
                 continue;
             } else {
-                return None;
+                break None;
             }
         }
-        if pos == $src.len() {
-            return None;
-        } else {
-            pos
-        }
     }};
 }
 
@@ -111,16 +100,6 @@ macro_rules! cond_eq {
     };
 }
 
-#[macro_export]
-macro_rules! position {
-    ($s:ident, $i:expr, $p:expr) => {
-        match $s[$i..].chars().position($p) {
-            Some(x) => x + $i,
-            None => return None,
-        }
-    };
-}
-
 #[macro_export]
 macro_rules! starts_with {
     ($s:ident, $p:expr) => {
@@ -144,13 +123,13 @@ macro_rules! skip_space {
 macro_rules! skip_empty_line {
     ($src:ident, $from:expr) => {{
         let mut pos = $from;
-        while pos < $src.len() {
-            if $src.as_bytes()[pos] != b'\n' {
-                break;
+        loop {
+            if pos >= $src.len() || $src.as_bytes()[pos] != b'\n' {
+                break pos;
+            } else {
+                pos += 1;
             }
-            pos += 1;
         }
-        pos
     }};
 }