Fix broken links and default dark theme

Author: ehsanmok

book/book.toml

@@ -9,6 +9,7 @@ version = "0.1"
 [output.html]
 google-analytics = "UA-168768722-1"
 additional-css = ["theme/custom.css"]
+preferred-dark-theme = "Rust"
 
 [output.html.search]
 enable = true

book/src/01_calculator/exercise.md

@@ -4,4 +4,4 @@ To get most out of this chapter, it is recommended to at least try the first exe
 
 1. Add support for multiplication and division to the calculator and allow computations on floating numbers `f32`. Can you include standard operator precedence?
 2. JIT with [cranelift-simplejit](https://docs.rs/cranelift-simplejit/0.64.0/cranelift_simplejit/)
-3. JIT with [gcc-jit](http://swgillespie.me/gccjit.rs/gccjit/)
+3. JIT with [gcc-jit](https://github.com/swgillespie/gccjit.rs)

book/src/01_calculator/grammar_lexer_parser.md

@@ -27,7 +27,7 @@ This grammar basically defines the syntax and semantics where
 * unary or binary expressions are made of `Term` and `Operator` (`"+"` and `"-"`)
 * the only *atom* is integer `Int`
 
-Given our grammar, we will use [pest](https://pest.rs/) which is a powerful *parser generator* of PEG grammars. (For more details on pest, checkout the [pest book](https://pest.rs/book/))
+Given our grammar, we will use [pest](https://bitbegin.github.io/pest-rs/) which is a powerful *parser generator* of PEG grammars. (For more details on pest, checkout the [pest book](https://bitbegin.github.io/pest-rs/book/)
 
 `pest` *derives* the parser `CalcParser::parse` from our grammar
 

book/src/01_calculator/jit_intro.md

@@ -10,4 +10,4 @@ We will use [inkwell](https://github.com/TheDan64/inkwell) which provides a safe
 
 ### Alternatives
 
-Other code generators that you can use (see the [exercises](./exercise.md)) in this book (not at mature as LLVM) are [cratelift-simpljit](https://docs.rs/cranelift-simplejit/0.64.0/cranelift_simplejit/index.html) and [gcc-jit](http://swgillespie.me/gccjit.rs/gccjit/).
+Other code generators that you can use (see the [exercises](./exercise.md)) in this book (not at mature as LLVM) are [cratelift-simpljit](https://docs.rs/cranelift-simplejit/0.64.0/cranelift_simplejit/index.html) and [gcc-jit](https://github.com/swgillespie/gccjit.rs).

book/src/intro.md

@@ -35,7 +35,7 @@ The following are my guidelines
 Here is the outline of the contents
 
 * [Crash Course on Computing](./crash_course.md) which we briefly set up the definitions and foundations
-* We create our first programming language `Calc` that supports simple integer addition and subtraction. The simplicity allows us to touch a lot of important topics. We will use [PEG](https://en.wikipedia.org/wiki/Parsing_expression_grammar) to define our grammar, [pest](https://pest.rs) to generate our `CalcParser` and explain what AST is and interpreting the AST means. Next, we will introduce JIT compilation and use [inkwell](https://github.com/TheDan64/inkwell) to JIT compile our `Calc` language from its AST. To show an alternative compilation approach, we will create a Virtual Machine and a Runtime environment and discuss its features. Finally, we will write a simple REPL for our `Calc` language and test out different execution paths.
+* We create our first programming language `Calc` that supports simple integer addition and subtraction. The simplicity allows us to touch a lot of important topics. We will use [PEG](https://en.wikipedia.org/wiki/Parsing_expression_grammar) to define our grammar, [pest](https://bitbegin.github.io/pest-rs/) to generate our `CalcParser` and explain what AST is and interpreting the AST means. Next, we will introduce JIT compilation and use [inkwell](https://github.com/TheDan64/inkwell) to JIT compile our `Calc` language from its AST. To show an alternative compilation approach, we will create a Virtual Machine and a Runtime environment and discuss its features. Finally, we will write a simple REPL for our `Calc` language and test out different execution paths.
 * TODO: We will introduce `Jeslang` (a statically typed language) and gradually work our way up from `Calc` language to create `Jeslang` together
 * TODO: Object system and object oriented programming
 * TODO: Functional language