improve readability and stuff idk and also rustfmt

src/bin/ckconf.rs

@@ -13,10 +13,12 @@ fn main() {
 
     let s = fs::read_to_string(&argv[1]).expect("Cannot open file");
     match Config::parse(s.chars()) {
-        Ok(conf) => for k in conf.keys() {
-            println!("{:?}", conf.get_node(k));
-        },
-        Err(e) => panic!("{:?}", e.msg)
+        Ok(conf) => {
+            for k in conf.keys() {
+                println!("{:?}", conf.get_node(k));
+            }
+        }
+        Err(e) => panic!("{:?}", e.msg),
     }
 }
 

src/lex/cursor.rs

@@ -32,25 +32,22 @@ impl<'a> Cursor<'a> {
     pub fn advance_by(&mut self, n: usize) -> Result<(), usize> {
         for i in 0..n {
             if self.next() == None {
-                return Err(i)
+                return Err(i);
             }
         }
 
         Ok(())
     }
 
-    pub fn next_until(&mut self, test: fn (c: char) -> bool) -> String {
+    pub fn next_until(&mut self, test: fn(c: char) -> bool) -> String {
         let mut s = String::new();
-    
-        for _ in 0.. {
-            match self.peek() {
-                Some(c) => if test(c) {
-                    break;
-                } else {
-                    s.push(c);
-                    self.next();
-                },
-                None => break,
+
+        while let Some(c) = self.peek() {
+            if test(c) {
+                break;
+            } else {
+                s.push(c);
+                self.next();
             }
         }
 

src/lex/mod.rs

@@ -1,10 +1,11 @@
 // See the end of this file for copyright and license terms.
 
+use std::any::Any;
 use std::str::Chars;
 
-mod cursor;
 use cursor::Cursor;
-use std::any::Any;
+
+mod cursor;
 
 pub struct Lexer<'a> {
     cursor: Cursor<'a>,
@@ -61,7 +62,7 @@ impl Iterator for Lexer<'_> {
 
             '"' => self.read_string(),
 
-            c @ '0'..='9' => Ok(self.read_int_rest(c)),
+            c @ '1'..='9' => Ok(self.read_int_rest(c)),
 
             c @ 'a'..='z' | c @ 'A'..='Z' => Ok(self.read_keyword_or_ident(c)),
 
@@ -70,7 +71,7 @@ impl Iterator for Lexer<'_> {
     }
 }
 
-impl <'a> Lexer<'a> {
+impl<'a> Lexer<'a> {
     pub const fn new(stream: Chars<'a>) -> Lexer<'a> {
         Lexer {
             cursor: Cursor::new(stream),
@@ -97,17 +98,21 @@ impl <'a> Lexer<'a> {
 
     fn read_keyword_or_ident(&mut self, first: char) -> Token {
         let kind = match first {
-            't' => if self.skip_if_match(String::from("rue")) {
-                TokenKind::TrueKeyword
-            } else {
-                TokenKind::Ident(self.read_ident_rest(first))
-            },
+            't' => {
+                if self.skip_if_match(String::from("rue")) {
+                    TokenKind::TrueKeyword
+                } else {
+                    TokenKind::Ident(self.read_ident_rest(first))
+                }
+            }
 
-            'f' => if self.skip_if_match(String::from("alse")) {
-                TokenKind::FalseKeyword
-            } else {
-                TokenKind::Ident(self.read_ident_rest(first))
-            },
+            'f' => {
+                if self.skip_if_match(String::from("alse")) {
+                    TokenKind::FalseKeyword
+                } else {
+                    TokenKind::Ident(self.read_ident_rest(first))
+                }
+            }
 
             _ => TokenKind::Ident(self.read_ident_rest(first)),
         };
@@ -118,10 +123,10 @@ impl <'a> Lexer<'a> {
     fn read_ident_rest(&mut self, first: char) -> String {
         let mut s = String::from(first);
 
-        s += self.cursor.next_until(|c| match c {
-            'A'..='Z' | 'a'..='z' | '0'..='9' | '_' => false,
-            _ => true,
-        }).as_str();
+        s += self
+            .cursor
+            .next_until(|c| !matches!(c, 'A'..='Z' | 'a'..='z' | '0'..='9' | '_'))
+            .as_str();
 
         s
     }
@@ -158,26 +163,17 @@ impl <'a> Lexer<'a> {
 
     fn read_int_rest(&mut self, first: char) -> Token {
         let mut s = String::from(first);
-
-        loop {
-            match self.cursor.peek() {
-                Some(c @ '0'..='9') => {
-                    s.push(c);
-                    self.cursor.next();
-                },
-                _ => break,
-            }
-        }
+        s.push_str(&self.cursor.next_until(|c| !matches!(c, '0'..='9')));
 
         self.make_token(TokenKind::IntLiteral(
-            s.parse().expect("this shouldn't be possible lol")
+            s.parse().expect("this shouldn't be possible lol"),
         ))
     }
 
     fn read_whitespace(&mut self) -> Option<Token> {
         let ws = self.cursor.next_until(|c| !is_whitespace(c));
 
-        if ws.len() > 0 {
+        if !ws.is_empty() {
             Some(self.make_token(TokenKind::Whitespace(ws)))
         } else {
             None
@@ -193,13 +189,15 @@ impl <'a> Lexer<'a> {
             }
         }
 
-        self.cursor.advance_by(s.len()).expect("this shouldn't be possible lol");
+        self.cursor
+            .advance_by(s.len())
+            .expect("this shouldn't be possible lol");
         true
     }
 
     fn make_token(&mut self, kind: TokenKind) -> Token {
         let t = Token {
-            kind: kind,
+            kind,
             line: self.token_line,
             col: self.token_col,
         };
@@ -212,10 +210,7 @@ impl <'a> Lexer<'a> {
 }
 
 fn is_whitespace(c: char) -> bool {
-    match c {
-        ' ' | '\n' | '\t' => true,
-        _ => false,
-    }
+    matches!(c, ' ' | '\n' | '\t')
 }
 
 pub struct SyntaxError {

src/lib.rs

@@ -1,12 +1,13 @@
 // See the end of this file for copyright and license terms.
 
-use std::str::Chars;
 use std::collections::HashMap;
+use std::str::Chars;
 
 pub mod lex;
 use crate::lex::{Lexer, SyntaxError};
 
 pub mod parser;
+
 use parser::Parser;
 use std::collections::hash_map::Keys;
 
@@ -25,14 +26,12 @@ impl Config {
                 Ok(node) => {
                     let name = node.name.clone();
                     nodes.insert(name, node);
-                },
+                }
                 Err(err) => return Err(err),
             }
         }
 
-        Ok(Config {
-            nodes
-        })
+        Ok(Config { nodes })
     }
 
     pub fn keys(&self) -> Keys<String, Node> {

src/parser.rs

@@ -1,69 +1,72 @@
 // See the end of this file for copyright and license terms.
 
-use crate::lex::{Token, TokenKind, Lexer, SyntaxError};
-use crate::{Node, NodeVal};
 use std::any::Any;
 
+use crate::lex::{Lexer, SyntaxError, Token, TokenKind};
+use crate::{Node, NodeVal};
+
 pub struct Parser<'a> {
     lexer: Lexer<'a>,
 }
 
-impl <'a> Parser<'a> {
+impl<'a> Parser<'a> {
     pub const fn new(lexer: Lexer<'a>) -> Parser<'a> {
-        Parser {
-            lexer
-        }
+        Parser { lexer }
     }
 
     fn parse_node(&mut self) -> Option<Result<Node, SyntaxError>> {
-        Some(self.lexer.next()?.and_then(|token| match token.kind {
-            TokenKind::Ident(name) => {
-                self.require_kind(TokenKind::Eq ).and_then(|_| {
-                    self.require_next()
-                }).and_then(|token| match token.kind {
-                    TokenKind::TrueKeyword => self.node_result(name, NodeVal::Bool(true)),
-                    TokenKind::FalseKeyword => self.node_result(name, NodeVal::Bool(false)),
-                    TokenKind::IntLiteral(i) => self.node_result(name, NodeVal::Int(i)),
-                    TokenKind::StringLiteral(s) => self.node_result(name, NodeVal::String(s)),
-                    _ => self.lexer.syntax_error(String::from("Expected a value")),
-                }).and_then(|node| {
-                    self.require_kind(TokenKind::Semi).and_then(|_| Ok(node))
-                })
-            },
-            _ => self.lexer.syntax_error(String::from("Expected identifier")),
+        Some(self.lexer.next()?.and_then(|token| {
+            match token.kind {
+                TokenKind::Ident(name) => self
+                    .require_kind(TokenKind::Eq)
+                    .and_then(|_| self.require_next())
+                    .and_then(|token| match token.kind {
+                        TokenKind::TrueKeyword => self.node_result(name, NodeVal::Bool(true)),
+                        TokenKind::FalseKeyword => self.node_result(name, NodeVal::Bool(false)),
+                        TokenKind::IntLiteral(i) => self.node_result(name, NodeVal::Int(i)),
+                        TokenKind::StringLiteral(s) => self.node_result(name, NodeVal::String(s)),
+                        _ => self.lexer.syntax_error(String::from("Expected a value")),
+                    })
+                    .and_then(|node| self.require_kind(TokenKind::Semi).and_then(|_| Ok(node))),
+                _ => self.lexer.syntax_error(String::from("Expected identifier")),
+            }
         }))
     }
 
     fn require_kind(&mut self, kind: TokenKind) -> Result<Token, SyntaxError> {
-        self.require_next().and_then(|token|
+        self.require_next().and_then(|token| {
             if token.kind.type_id() == kind.type_id() {
                 Ok(token)
             } else {
-                self.lexer.syntax_error(format!("Expected {:?}, got {:?}", kind, token.kind))
+                self.lexer
+                    .syntax_error(format!("Expected {:?}, got {:?}", kind, token.kind))
             }
-        )
+        })
     }
 
     fn require_next(&mut self) -> Result<Token, SyntaxError> {
         match self.lexer.next() {
             Some(result) => result,
-            None => self.lexer.syntax_error(String::from("Unexpected end of file")),
+            None => self
+                .lexer
+                .syntax_error(String::from("Unexpected end of file")),
         }
     }
 
+    #[allow(clippy::unnecessary_wraps)]  // Convenience wrapper
     fn node_result<T>(&self, name: String, val: NodeVal) -> Result<Node, T> {
         Ok(self.make_node(name, val))
     }
 
     fn make_node(&self, name: String, val: NodeVal) -> Node {
         Node {
-            name: String::from(name),
+            name,
             val,
         }
     }
 }
 
-impl <'a> Iterator for Parser<'a> {
+impl<'a> Iterator for Parser<'a> {
     type Item = Result<Node, SyntaxError>;
 
     fn next(&mut self) -> Option<Result<Node, SyntaxError>> {