Move some types into better places 🧱

9 files changed, 230 insertions, 219 deletions

diff --git a/src/doc.rs b/src/doc.rs
index 5d3c1e14..3ffc7f8c 100644
--- a/src/doc.rs
+++ b/src/doc.rs
@@ -1,9 +1,10 @@
-//! Abstract representation of a typesetted document.
+//! Representation of typesetted documents.
 
 use crate::font::Font;
+use crate::engine::Size;
 
 
-/// A representation of a typesetted document.
+/// A complete typesetted document, which can be exported.
 #[derive(Debug, Clone, PartialEq)]
 pub struct Document {
     /// The pages of the document.
@@ -12,62 +13,6 @@ pub struct Document {
     pub fonts: Vec<Font>,
 }
 
-/// Default styles for a document.
-#[derive(Debug, Clone, PartialEq)]
-pub struct Style {
-    /// The width of the paper.
-    pub width: Size,
-    /// The height of the paper.
-    pub height: Size,
-
-    /// The left margin of the paper.
-    pub margin_left: Size,
-    /// The top margin of the paper.
-    pub margin_top: Size,
-    /// The right margin of the paper.
-    pub margin_right: Size,
-    /// The bottom margin of the paper.
-    pub margin_bottom: Size,
-
-    /// A fallback list of font families to use.
-    pub font_families: Vec<FontFamily>,
-    /// The font size.
-    pub font_size: f32,
-    /// The line spacing (as a multiple of the font size).
-    pub line_spacing: f32,
-}
-
-/// A family of fonts (either generic or named).
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum FontFamily {
-    SansSerif,
-    Serif,
-    Monospace,
-    Named(String),
-}
-
-impl Default for Style {
-    fn default() -> Style {
-        use FontFamily::*;
-        Style {
-            // A4 paper.
-            width: Size::from_mm(210.0),
-            height: Size::from_mm(297.0),
-
-            // Margins. A bit more on top and bottom.
-            margin_left: Size::from_cm(2.5),
-            margin_top: Size::from_cm(3.0),
-            margin_right: Size::from_cm(2.5),
-            margin_bottom: Size::from_cm(3.0),
-
-            // Default font family, font size and line spacing.
-            font_families: vec![SansSerif, Serif, Monospace],
-            font_size: 12.0,
-            line_spacing: 1.25,
-        }
-    }
-}
-
 /// A page with text contents in a document.
 #[derive(Debug, Clone, PartialEq)]
 pub struct Page {
@@ -96,144 +41,3 @@ pub enum TextCommand {
     /// Use the indexed font in the documents font list with a given font size.
     SetFont(usize, f32),
 }
-
-/// A general distance type that can convert between units.
-#[derive(Debug, Copy, Clone, PartialEq)]
-pub struct Size {
-    /// The size in typographic points (1/72 inches).
-    points: f32,
-}
-
-impl Size {
-    /// Create an zeroed size.
-    #[inline]
-    pub fn zero() -> Size { Size { points: 0.0 } }
-
-    /// Create a size from a number of points.
-    #[inline]
-    pub fn from_points(points: f32) -> Size { Size { points } }
-
-    /// Create a size from a number of inches.
-    #[inline]
-    pub fn from_inches(inches: f32) -> Size { Size { points: 72.0 * inches } }
-
-    /// Create a size from a number of millimeters.
-    #[inline]
-    pub fn from_mm(mm: f32) -> Size { Size { points: 2.83465 * mm  } }
-
-    /// Create a size from a number of centimeters.
-    #[inline]
-    pub fn from_cm(cm: f32) -> Size { Size { points: 28.3465 * cm } }
-
-    /// Create a size from a number of points.
-    #[inline]
-    pub fn to_points(&self) -> f32 { self.points }
-
-    /// Create a size from a number of inches.
-    #[inline]
-    pub fn to_inches(&self) -> f32 { self.points * 0.0138889 }
-
-    /// Create a size from a number of millimeters.
-    #[inline]
-    pub fn to_mm(&self) -> f32 { self.points * 0.352778 }
-
-    /// Create a size from a number of centimeters.
-    #[inline]
-    pub fn to_cm(&self) -> f32 { self.points * 0.0352778 }
-}
-
-mod size {
-    use super::Size;
-    use std::cmp::Ordering;
-    use std::fmt;
-    use std::iter::Sum;
-    use std::ops::*;
-
-    impl fmt::Display for Size {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-            write!(f, "{}pt", self.points)
-        }
-    }
-
-    macro_rules! impl_reflexive {
-        ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident) => {
-            impl $trait for Size {
-                type Output = Size;
-
-                #[inline]
-                fn $func(self, other: Size) -> Size {
-                    Size { points: $trait::$func(self.points, other.points) }
-                }
-            }
-
-            impl $assign_trait for Size {
-                #[inline]
-                fn $assign_func(&mut self, other: Size) {
-                    $assign_trait::$assign_func(&mut self.points, other.points);
-                }
-            }
-        };
-    }
-
-    macro_rules! impl_num_back {
-        ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident, $ty:ty) => {
-            impl $trait<$ty> for Size {
-                type Output = Size;
-
-                #[inline]
-                fn $func(self, other: $ty) -> Size {
-                    Size { points: $trait::$func(self.points, other as f32) }
-                }
-            }
-
-            impl $assign_trait<$ty> for Size {
-                #[inline]
-                fn $assign_func(&mut self, other: $ty) {
-                    $assign_trait::$assign_func(&mut self.points, other as f32);
-                }
-            }
-        };
-    }
-
-    macro_rules! impl_num_both {
-        ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident, $ty:ty) => {
-            impl_num_back!($trait, $func, $assign_trait, $assign_func, $ty);
-
-            impl $trait<Size> for $ty {
-                type Output = Size;
-
-                #[inline]
-                fn $func(self, other: Size) -> Size {
-                    Size { points: $trait::$func(self as f32, other.points) }
-                }
-            }
-        };
-    }
-
-    impl Neg for Size {
-        type Output = Size;
-
-        fn neg(self) -> Size {
-            Size { points: -self.points }
-        }
-    }
-
-    impl_reflexive!(Add, add, AddAssign, add_assign);
-    impl_reflexive!(Sub, sub, SubAssign, sub_assign);
-    impl_num_both!(Mul, mul, MulAssign, mul_assign, f32);
-    impl_num_both!(Mul, mul, MulAssign, mul_assign, i32);
-    impl_num_back!(Div, div, DivAssign, div_assign, f32);
-    impl_num_back!(Div, div, DivAssign, div_assign, i32);
-
-    impl PartialOrd for Size {
-        fn partial_cmp(&self, other: &Size) -> Option<Ordering> {
-            self.points.partial_cmp(&other.points)
-        }
-    }
-
-    impl Sum for Size {
-        fn sum<I>(iter: I) -> Size where I: Iterator<Item=Size> {
-            iter.fold(Size::zero(), Add::add)
-        }
-    }
-}
diff --git a/src/engine.rs b/src/engine/mod.rs
index ff89d674..f121ac82 100644
--- a/src/engine.rs
+++ b/src/engine/mod.rs
@@ -1,10 +1,13 @@
 //! Core typesetting engine.
 
 use crate::syntax::{SyntaxTree, Node};
-use crate::doc::{Document, Size, Page, Text, TextCommand};
-use crate::font::{Font, FontConfig, FontError};
+use crate::doc::{Document, Page, Text, TextCommand};
+use crate::font::{Font, FontFamily, FontConfig, FontError};
 use crate::Context;
 
+mod size;
+pub use size::Size;
+
 
 /// The core typesetting engine, transforming an abstract syntax tree into a document.
 pub(crate) struct Engine<'a> {
@@ -138,6 +141,53 @@ impl<'a> Engine<'a> {
     }
 }
 
+/// Default styles for a document.
+#[derive(Debug, Clone, PartialEq)]
+pub struct Style {
+    /// The width of the paper.
+    pub width: Size,
+    /// The height of the paper.
+    pub height: Size,
+
+    /// The left margin of the paper.
+    pub margin_left: Size,
+    /// The top margin of the paper.
+    pub margin_top: Size,
+    /// The right margin of the paper.
+    pub margin_right: Size,
+    /// The bottom margin of the paper.
+    pub margin_bottom: Size,
+
+    /// A fallback list of font families to use.
+    pub font_families: Vec<FontFamily>,
+    /// The font size.
+    pub font_size: f32,
+    /// The line spacing (as a multiple of the font size).
+    pub line_spacing: f32,
+}
+
+impl Default for Style {
+    fn default() -> Style {
+        use FontFamily::*;
+        Style {
+            // A4 paper.
+            width: Size::from_mm(210.0),
+            height: Size::from_mm(297.0),
+
+            // Margins. A bit more on top and bottom.
+            margin_left: Size::from_cm(2.5),
+            margin_top: Size::from_cm(3.0),
+            margin_right: Size::from_cm(2.5),
+            margin_bottom: Size::from_cm(3.0),
+
+            // Default font family, font size and line spacing.
+            font_families: vec![SansSerif, Serif, Monospace],
+            font_size: 12.0,
+            line_spacing: 1.25,
+        }
+    }
+}
+
 /// The error type for typesetting.
 pub enum TypesetError {
     /// There was no suitable font.
diff --git a/src/engine/size.rs b/src/engine/size.rs
new file mode 100644
index 00000000..a6624c57
--- /dev/null
+++ b/src/engine/size.rs
@@ -0,0 +1,144 @@
+use std::cmp::Ordering;
+use std::fmt::{self, Display, Debug, Formatter};
+use std::iter::Sum;
+use std::ops::*;
+
+
+/// A general distance type that can convert between units.
+#[derive(Copy, Clone, PartialEq)]
+pub struct Size {
+    /// The size in typographic points (1/72 inches).
+    points: f32,
+}
+
+impl Size {
+    /// Create an zeroed size.
+    #[inline]
+    pub fn zero() -> Size { Size { points: 0.0 } }
+
+    /// Create a size from a number of points.
+    #[inline]
+    pub fn from_points(points: f32) -> Size { Size { points } }
+
+    /// Create a size from a number of inches.
+    #[inline]
+    pub fn from_inches(inches: f32) -> Size { Size { points: 72.0 * inches } }
+
+    /// Create a size from a number of millimeters.
+    #[inline]
+    pub fn from_mm(mm: f32) -> Size { Size { points: 2.83465 * mm  } }
+
+    /// Create a size from a number of centimeters.
+    #[inline]
+    pub fn from_cm(cm: f32) -> Size { Size { points: 28.3465 * cm } }
+
+    /// Create a size from a number of points.
+    #[inline]
+    pub fn to_points(&self) -> f32 { self.points }
+
+    /// Create a size from a number of inches.
+    #[inline]
+    pub fn to_inches(&self) -> f32 { self.points * 0.0138889 }
+
+    /// Create a size from a number of millimeters.
+    #[inline]
+    pub fn to_mm(&self) -> f32 { self.points * 0.352778 }
+
+    /// Create a size from a number of centimeters.
+    #[inline]
+    pub fn to_cm(&self) -> f32 { self.points * 0.0352778 }
+}
+
+impl Display for Size {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{}pt", self.points)
+    }
+}
+
+impl Debug for Size {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+impl PartialOrd for Size {
+    fn partial_cmp(&self, other: &Size) -> Option<Ordering> {
+        self.points.partial_cmp(&other.points)
+    }
+}
+
+impl Neg for Size {
+    type Output = Size;
+
+    fn neg(self) -> Size {
+        Size { points: -self.points }
+    }
+}
+
+impl Sum for Size {
+    fn sum<I>(iter: I) -> Size where I: Iterator<Item=Size> {
+        iter.fold(Size::zero(), Add::add)
+    }
+}
+
+macro_rules! impl_reflexive {
+    ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident) => {
+        impl $trait for Size {
+            type Output = Size;
+
+            #[inline]
+            fn $func(self, other: Size) -> Size {
+                Size { points: $trait::$func(self.points, other.points) }
+            }
+        }
+
+        impl $assign_trait for Size {
+            #[inline]
+            fn $assign_func(&mut self, other: Size) {
+                $assign_trait::$assign_func(&mut self.points, other.points);
+            }
+        }
+    };
+}
+
+macro_rules! impl_num_back {
+    ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident, $ty:ty) => {
+        impl $trait<$ty> for Size {
+            type Output = Size;
+
+            #[inline]
+            fn $func(self, other: $ty) -> Size {
+                Size { points: $trait::$func(self.points, other as f32) }
+            }
+        }
+
+        impl $assign_trait<$ty> for Size {
+            #[inline]
+            fn $assign_func(&mut self, other: $ty) {
+                $assign_trait::$assign_func(&mut self.points, other as f32);
+            }
+        }
+    };
+}
+
+macro_rules! impl_num_both {
+    ($trait:ident, $func:ident, $assign_trait:ident, $assign_func:ident, $ty:ty) => {
+        impl_num_back!($trait, $func, $assign_trait, $assign_func, $ty);
+
+        impl $trait<Size> for $ty {
+            type Output = Size;
+
+            #[inline]
+            fn $func(self, other: Size) -> Size {
+                Size { points: $trait::$func(self as f32, other.points) }
+            }
+        }
+    };
+}
+
+impl_reflexive!(Add, add, AddAssign, add_assign);
+impl_reflexive!(Sub, sub, SubAssign, sub_assign);
+impl_num_both!(Mul, mul, MulAssign, mul_assign, f32);
+impl_num_both!(Mul, mul, MulAssign, mul_assign, i32);
+impl_num_back!(Div, div, DivAssign, div_assign, f32);
+impl_num_back!(Div, div, DivAssign, div_assign, i32);
diff --git a/src/error.rs b/src/error.rs
index cfdb1f0e..442971d0 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -1,3 +1,5 @@
+//! Error handling.
+
 /// Create an error type.
 macro_rules! error_type {
     (
diff --git a/src/export/pdf.rs b/src/export/pdf.rs
index 630a0501..cac60a87 100644
--- a/src/export/pdf.rs
+++ b/src/export/pdf.rs
@@ -6,8 +6,9 @@ use pdf::{PdfWriter, Ref, Rect, Version, Trailer, Content};
 use pdf::doc::{Catalog, PageTree, Page, Resource, Text};
 use pdf::font::{Type0Font, CIDFont, CIDFontType, CIDSystemInfo, FontDescriptor, FontFlags};
 use pdf::font::{GlyphUnit, CMapEncoding, WidthRecord, FontStream, EmbeddedFontType};
-use crate::doc::{Document, Size, Text as DocText, TextCommand};
+use crate::doc::{Document, Text as DocText, TextCommand};
 use crate::font::{Font, FontError};
+use crate::engine::Size;
 
 
 /// Exports documents into _PDFs_.
diff --git a/src/font.rs b/src/font.rs
index 294c2b7e..37346a3e 100644
--- a/src/font.rs
+++ b/src/font.rs
@@ -1,6 +1,4 @@
-//! Font loading, utility and subsetting.
-
-#![macro_use]
+//! Font loading and transforming.
 
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
@@ -9,7 +7,7 @@ use byteorder::{BE, ReadBytesExt, WriteBytesExt};
 use opentype::{Error as OpentypeError, OpenTypeReader, Outlines, TableRecord, Tag};
 use opentype::tables::{Header, Name, CharMap, MaximumProfile, HorizontalMetrics, Post, OS2};
 use opentype::global::{MacStyleFlags, NameEntry};
-use crate::doc::{Size, FontFamily};
+use crate::engine::Size;
 
 
 /// An font wrapper which allows to subset a font.
@@ -54,8 +52,8 @@ impl Font {
     /// Create a new font from a font program.
     pub fn new(program: Vec<u8>) -> FontResult<Font> {
         // Create opentype reader to parse font tables
-        let mut readable = Cursor::new(&program);
-        let mut reader = OpenTypeReader::new(&mut readable);
+        let cursor = Cursor::new(&program);
+        let mut reader = OpenTypeReader::new(cursor);
 
         // Read the relevant tables
         // (all of these are required by the OpenType specification)
@@ -586,8 +584,6 @@ impl<T> TakeInvalid<T> for Option<T> {
     }
 }
 
-///////////////////////////////////////////////////////////////////////////////
-
 /// A type that provides fonts matching given criteria.
 pub trait FontProvider {
     /// Returns a font matching the configuration
@@ -599,8 +595,18 @@ pub trait FontProvider {
 ///
 /// Automatically implemented for all types that are [`Read`] and [`Seek`].
 pub trait FontSource: Read + Seek {}
+
 impl<T> FontSource for T where T: Read + Seek {}
 
+/// A family of fonts (either generic or named).
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum FontFamily {
+    SansSerif,
+    Serif,
+    Monospace,
+    Named(String),
+}
+
 /// Criteria to filter fonts.
 #[derive(Debug, Clone, PartialEq)]
 pub struct FontConfig {
@@ -694,8 +700,8 @@ impl FileFontDescriptor<'_> {
 #[macro_export]
 macro_rules! file_font {
     ($family:expr, [$($generic:ident),*], $path:expr, $bold:expr, $italic:expr) => {{
-        let mut families = vec![$crate::doc::FontFamily::Named($family.to_string())];
-        families.extend([$($crate::doc::FontFamily::$generic),*].iter().cloned());
+        let mut families = vec![$crate::font::FontFamily::Named($family.to_string())];
+        families.extend([$($crate::font::FontFamily::$generic),*].iter().cloned());
         $crate::font::FileFontDescriptor {
             path: std::path::Path::new($path),
             families,
diff --git a/src/lib.rs b/src/lib.rs
index 4434f62f..9f37efc2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -33,16 +33,19 @@
 //! let document = compiler.typeset(src).unwrap();
 //!
 //! // Export the document into a PDF file.
-//! let mut file = File::create("hello-typeset.pdf").unwrap();
+//! # /*
+//! let file = File::create("hello-typeset.pdf").unwrap();
+//! # */
+//! # let file = File::create("../target/typeset-hello.pdf").unwrap();
 //! let exporter = PdfExporter::new();
-//! exporter.export(&document, &mut file).unwrap();
+//! exporter.export(&document, file).unwrap();
 //! ```
 
 use crate::syntax::SyntaxTree;
 use crate::parsing::{Tokens, Parser, ParseError};
-use crate::doc::{Document, Style};
+use crate::doc::Document;
 use crate::font::FontProvider;
-use crate::engine::{Engine, TypesetError};
+use crate::engine::{Engine, Style, TypesetError};
 
 #[macro_use]
 mod error;
@@ -50,6 +53,7 @@ mod utility;
 pub mod doc;
 pub mod engine;
 pub mod export;
+#[macro_use]
 pub mod font;
 pub mod parsing;
 pub mod syntax;
@@ -135,6 +139,7 @@ error_type! {
     from: (TypesetError, Error::Typeset(err)),
 }
 
+
 #[cfg(test)]
 mod test {
     use std::fs::File;
diff --git a/src/parsing.rs b/src/parsing.rs
index 2737fde4..92eaae75 100644
--- a/src/parsing.rs
+++ b/src/parsing.rs
@@ -1,4 +1,4 @@
-//! Parsing of source code into tokens and syntax trees.
+//! Tokenization and parsing of source code into syntax trees.
 
 use std::fmt;
 use std::iter::Peekable;
@@ -475,7 +475,6 @@ mod token_tests {
     }
 }
 
-
 #[cfg(test)]
 mod parse_tests {
     use super::*;
diff --git a/src/syntax.rs b/src/syntax.rs
index 38e5a60e..56e11605 100644
--- a/src/syntax.rs
+++ b/src/syntax.rs
@@ -1,4 +1,4 @@
-//! Token and abstract syntax tree representations.
+//! Tokenized and syntax tree representations of source code.
 
 
 /// A logical unit of the incoming text stream.