453 lines
13 KiB
Rust

use smallvec::{smallvec, SmallVec};
use typst_syntax::Spanned;
use typst_utils::{default_math_class, Numeric};
use unicode_math_class::MathClass;
use crate::diag::{bail, At, HintedStrResult, StrResult};
use crate::foundations::{
array, cast, dict, elem, Array, Content, Dict, Fold, NoneValue, Resolve, Smart,
StyleChain, Symbol, Value,
};
use crate::layout::{Abs, Em, HAlignment, Length, Rel};
use crate::math::Mathy;
use crate::visualize::Stroke;
const DEFAULT_ROW_GAP: Em = Em::new(0.2);
const DEFAULT_COL_GAP: Em = Em::new(0.5);
/// A column vector.
///
/// Content in the vector's elements can be aligned with the
/// [`align`]($math.vec.align) parameter, or the `&` symbol.
///
/// # Example
/// ```example
/// $ vec(a, b, c) dot vec(1, 2, 3)
/// = a + 2b + 3c $
/// ```
#[elem(title = "Vector", Mathy)]
pub struct VecElem {
/// The delimiter to use.
///
/// Can be a single character specifying the left delimiter, in which case
/// the right delimiter is inferred. Otherwise, can be an array containing a
/// left and a right delimiter.
///
/// ```example
/// #set math.vec(delim: "[")
/// $ vec(1, 2) $
/// ```
#[default(DelimiterPair::PAREN)]
pub delim: DelimiterPair,
/// The horizontal alignment that each element should have.
///
/// ```example
/// #set math.vec(align: right)
/// $ vec(-1, 1, -1) $
/// ```
#[resolve]
#[default(HAlignment::Center)]
pub align: HAlignment,
/// The gap between elements.
///
/// ```example
/// #set math.vec(gap: 1em)
/// $ vec(1, 2) $
/// ```
#[resolve]
#[default(DEFAULT_ROW_GAP.into())]
pub gap: Rel<Length>,
/// The elements of the vector.
#[variadic]
pub children: Vec<Content>,
}
/// A matrix.
///
/// The elements of a row should be separated by commas, while the rows
/// themselves should be separated by semicolons. The semicolon syntax merges
/// preceding arguments separated by commas into an array. You can also use this
/// special syntax of math function calls to define custom functions that take
/// 2D data.
///
/// Content in cells can be aligned with the [`align`]($math.mat.align)
/// parameter, or content in cells that are in the same row can be aligned with
/// the `&` symbol.
///
/// # Example
/// ```example
/// $ mat(
/// 1, 2, ..., 10;
/// 2, 2, ..., 10;
/// dots.v, dots.v, dots.down, dots.v;
/// 10, 10, ..., 10;
/// ) $
/// ```
#[elem(title = "Matrix", Mathy)]
pub struct MatElem {
/// The delimiter to use.
///
/// Can be a single character specifying the left delimiter, in which case
/// the right delimiter is inferred. Otherwise, can be an array containing a
/// left and a right delimiter.
///
/// ```example
/// #set math.mat(delim: "[")
/// $ mat(1, 2; 3, 4) $
/// ```
#[default(DelimiterPair::PAREN)]
pub delim: DelimiterPair,
/// The horizontal alignment that each cell should have.
///
/// ```example
/// #set math.mat(align: right)
/// $ mat(-1, 1, 1; 1, -1, 1; 1, 1, -1) $
/// ```
#[resolve]
#[default(HAlignment::Center)]
pub align: HAlignment,
/// Draws augmentation lines in a matrix.
///
/// - `{none}`: No lines are drawn.
/// - A single number: A vertical augmentation line is drawn
/// after the specified column number. Negative numbers start from the end.
/// - A dictionary: With a dictionary, multiple augmentation lines can be
/// drawn both horizontally and vertically. Additionally, the style of the
/// lines can be set. The dictionary can contain the following keys:
/// - `hline`: The offsets at which horizontal lines should be drawn.
/// For example, an offset of `2` would result in a horizontal line
/// being drawn after the second row of the matrix. Accepts either an
/// integer for a single line, or an array of integers
/// for multiple lines. Like for a single number, negative numbers start from the end.
/// - `vline`: The offsets at which vertical lines should be drawn.
/// For example, an offset of `2` would result in a vertical line being
/// drawn after the second column of the matrix. Accepts either an
/// integer for a single line, or an array of integers
/// for multiple lines. Like for a single number, negative numbers start from the end.
/// - `stroke`: How to [stroke]($stroke) the line. If set to `{auto}`,
/// takes on a thickness of 0.05em and square line caps.
///
/// ```example
/// $ mat(1, 0, 1; 0, 1, 2; augment: #2) $
/// // Equivalent to:
/// $ mat(1, 0, 1; 0, 1, 2; augment: #(-1)) $
/// ```
///
/// ```example
/// $ mat(0, 0, 0; 1, 1, 1; augment: #(hline: 1, stroke: 2pt + green)) $
/// ```
#[resolve]
#[fold]
pub augment: Option<Augment>,
/// The gap between rows and columns.
///
/// This is a shorthand to set `row-gap` and `column-gap` to the same value.
///
/// ```example
/// #set math.mat(gap: 1em)
/// $ mat(1, 2; 3, 4) $
/// ```
#[external]
pub gap: Rel<Length>,
/// The gap between rows.
///
/// ```example
/// #set math.mat(row-gap: 1em)
/// $ mat(1, 2; 3, 4) $
/// ```
#[resolve]
#[parse(
let gap = args.named("gap")?;
args.named("row-gap")?.or(gap)
)]
#[default(DEFAULT_ROW_GAP.into())]
pub row_gap: Rel<Length>,
/// The gap between columns.
///
/// ```example
/// #set math.mat(column-gap: 1em)
/// $ mat(1, 2; 3, 4) $
/// ```
#[resolve]
#[parse(args.named("column-gap")?.or(gap))]
#[default(DEFAULT_COL_GAP.into())]
pub column_gap: Rel<Length>,
/// An array of arrays with the rows of the matrix.
///
/// ```example
/// #let data = ((1, 2, 3), (4, 5, 6))
/// #let matrix = math.mat(..data)
/// $ v := matrix $
/// ```
#[variadic]
#[parse(
let mut rows = vec![];
let mut width = 0;
let values = args.all::<Spanned<Value>>()?;
if values.iter().any(|spanned| matches!(spanned.v, Value::Array(_))) {
for Spanned { v, span } in values {
let array = v.cast::<Array>().at(span)?;
let row: Vec<_> = array.into_iter().map(Value::display).collect();
width = width.max(row.len());
rows.push(row);
}
} else {
rows = vec![values.into_iter().map(|spanned| spanned.v.display()).collect()];
}
for row in &mut rows {
if row.len() < width {
row.resize(width, Content::empty());
}
}
rows
)]
pub rows: Vec<Vec<Content>>,
}
/// A case distinction.
///
/// Content across different branches can be aligned with the `&` symbol.
///
/// # Example
/// ```example
/// $ f(x, y) := cases(
/// 1 "if" (x dot y)/2 <= 0,
/// 2 "if" x "is even",
/// 3 "if" x in NN,
/// 4 "else",
/// ) $
/// ```
#[elem(Mathy)]
pub struct CasesElem {
/// The delimiter to use.
///
/// Can be a single character specifying the left delimiter, in which case
/// the right delimiter is inferred. Otherwise, can be an array containing a
/// left and a right delimiter.
///
/// ```example
/// #set math.cases(delim: "[")
/// $ x = cases(1, 2) $
/// ```
#[default(DelimiterPair::BRACE)]
pub delim: DelimiterPair,
/// Whether the direction of cases should be reversed.
///
/// ```example
/// #set math.cases(reverse: true)
/// $ cases(1, 2) = x $
/// ```
#[default(false)]
pub reverse: bool,
/// The gap between branches.
///
/// ```example
/// #set math.cases(gap: 1em)
/// $ x = cases(1, 2) $
/// ```
#[resolve]
#[default(DEFAULT_ROW_GAP.into())]
pub gap: Rel<Length>,
/// The branches of the case distinction.
#[variadic]
pub children: Vec<Content>,
}
/// A delimiter is a single character that is used to delimit a matrix, vector
/// or cases. The character has to be a Unicode codepoint tagged as a math
/// "opening", "closing" or "fence".
///
/// Typically, the delimiter is stretched to fit the height of whatever it
/// delimits.
#[derive(Debug, Default, Copy, Clone, Eq, PartialEq, Hash)]
pub struct Delimiter(Option<char>);
cast! {
Delimiter,
self => self.0.into_value(),
_: NoneValue => Self::none(),
v: Symbol => Self::char(v.get())?,
v: char => Self::char(v)?,
}
impl Delimiter {
pub fn none() -> Self {
Self(None)
}
pub fn char(c: char) -> StrResult<Self> {
if !matches!(
default_math_class(c),
Some(MathClass::Opening | MathClass::Closing | MathClass::Fence),
) {
bail!("invalid delimiter: \"{}\"", c)
}
Ok(Self(Some(c)))
}
pub fn get(self) -> Option<char> {
self.0
}
pub fn find_matching(self) -> Self {
match self.0 {
None => Self::none(),
Some('[') => Self(Some(']')),
Some(']') => Self(Some('[')),
Some('{') => Self(Some('}')),
Some('}') => Self(Some('{')),
Some(c) => match default_math_class(c) {
Some(MathClass::Opening) => Self(char::from_u32(c as u32 + 1)),
Some(MathClass::Closing) => Self(char::from_u32(c as u32 - 1)),
_ => Self(Some(c)),
},
}
}
}
/// A pair of delimiters (one closing, one opening) used for matrices, vectors
/// and cases.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub struct DelimiterPair {
open: Delimiter,
close: Delimiter,
}
cast! {
DelimiterPair,
self => array![self.open, self.close].into_value(),
v: Array => match v.as_slice() {
[open, close] => Self {
open: open.clone().cast()?,
close: close.clone().cast()?,
},
_ => bail!("expected 2 delimiters, found {}", v.len())
},
v: Delimiter => Self { open: v, close: v.find_matching() }
}
impl DelimiterPair {
const PAREN: Self = Self {
open: Delimiter(Some('(')),
close: Delimiter(Some(')')),
};
const BRACE: Self = Self {
open: Delimiter(Some('{')),
close: Delimiter(Some('}')),
};
/// The delimiter's opening character.
pub fn open(self) -> Option<char> {
self.open.get()
}
/// The delimiter's closing character.
pub fn close(self) -> Option<char> {
self.close.get()
}
}
/// Parameters specifying how augmentation lines
/// should be drawn on a matrix.
#[derive(Debug, Default, Clone, PartialEq, Hash)]
pub struct Augment<T: Numeric = Length> {
pub hline: AugmentOffsets,
pub vline: AugmentOffsets,
pub stroke: Smart<Stroke<T>>,
}
impl<T: Numeric + Fold> Fold for Augment<T> {
fn fold(self, outer: Self) -> Self {
Self {
stroke: match (self.stroke, outer.stroke) {
(Smart::Custom(inner), Smart::Custom(outer)) => {
Smart::Custom(inner.fold(outer))
}
// Usually, folding an inner `auto` with an `outer` prefers
// the explicit `auto`. However, here `auto` means unspecified
// and thus we want `outer`.
(inner, outer) => inner.or(outer),
},
..self
}
}
}
impl Resolve for Augment {
type Output = Augment<Abs>;
fn resolve(self, styles: StyleChain) -> Self::Output {
Augment {
hline: self.hline,
vline: self.vline,
stroke: self.stroke.resolve(styles),
}
}
}
cast! {
Augment,
self => {
// if the stroke is auto and there is only one vertical line,
if self.stroke.is_auto() && self.hline.0.is_empty() && self.vline.0.len() == 1 {
return self.vline.0[0].into_value();
}
dict! {
"hline" => self.hline,
"vline" => self.vline,
"stroke" => self.stroke,
}.into_value()
},
v: isize => Augment {
hline: AugmentOffsets::default(),
vline: AugmentOffsets(smallvec![v]),
stroke: Smart::Auto,
},
mut dict: Dict => {
let mut take = |key| dict.take(key).ok().map(AugmentOffsets::from_value).transpose();
let hline = take("hline")?.unwrap_or_default();
let vline = take("vline")?.unwrap_or_default();
let stroke = dict.take("stroke")
.ok()
.map(Stroke::from_value)
.transpose()?
.map(Smart::Custom)
.unwrap_or(Smart::Auto);
Augment { hline, vline, stroke }
},
}
cast! {
Augment<Abs>,
self => self.into_value(),
}
/// The offsets at which augmentation lines should be drawn on a matrix.
#[derive(Debug, Default, Clone, Eq, PartialEq, Hash)]
pub struct AugmentOffsets(pub SmallVec<[isize; 1]>);
cast! {
AugmentOffsets,
self => self.0.into_value(),
v: isize => Self(smallvec![v]),
v: Array => Self(v.into_iter().map(Value::cast).collect::<HintedStrResult<_>>()?),
}