logos calculator example

src/tokens.rs

@@ -0,0 +1,57 @@
+use logos::{Lexer, Logos};
+
+#[derive(Logos, Debug, Clone, PartialEq)]
+#[logos(skip r"[ \t\r\n\f]+")] // Skips whitespace
+pub enum Token<'source> {
+    #[token("false", |_| false)]
+    #[token("true", |_| true)]
+    Bool(bool),
+
+    #[token("+")]
+    Add,
+
+    #[token("-")]
+    Substract,
+
+    #[token("*")]
+    Multiply,
+
+    #[token("/")]
+    Divide,
+
+    #[token("=")]
+    Equals,
+
+    #[token(":")]
+    Colon,
+
+    #[token("(")]
+    ParenBegin,
+
+    #[token(")")]
+    ParenEnd,
+
+    #[token("{")]
+    BraceBegin,
+
+    #[token("}")]
+    BraceEnd,
+
+    #[regex("[0-9]+", |lex| lex.slice().parse::<isize>().unwrap())]
+    Integer(isize),
+    
+    #[regex(r"[_a-zA-Z][_0-9a-zA-Z]*")]
+    Ident(&'source str),
+
+    #[regex(r#""([^"\\\x00-\x1F]|\\(["\\bnfrt/]|u[a-fA-F0-9]{4}))*""#, |lex| lex.slice().to_owned())]
+    String(String),
+
+    #[token("class")]
+    #[token("fun")]
+    #[token("var")]
+    #[token("if")]
+    #[token("else")]
+    Keyword(&'source str),
+}
+
+