You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
131 lines
3.2 KiB
JavaScript
131 lines
3.2 KiB
JavaScript
// @flow
|
|
/**
|
|
* This file contains information and classes for the various kinds of styles
|
|
* used in TeX. It provides a generic `Style` class, which holds information
|
|
* about a specific style. It then provides instances of all the different kinds
|
|
* of styles possible, and provides functions to move between them and get
|
|
* information about them.
|
|
*/
|
|
|
|
/**
|
|
* The main style class. Contains a unique id for the style, a size (which is
|
|
* the same for cramped and uncramped version of a style), and a cramped flag.
|
|
*/
|
|
class Style implements StyleInterface {
|
|
id: number;
|
|
size: number;
|
|
cramped: boolean;
|
|
|
|
constructor(id: number, size: number, cramped: boolean) {
|
|
this.id = id;
|
|
this.size = size;
|
|
this.cramped = cramped;
|
|
}
|
|
|
|
/**
|
|
* Get the style of a superscript given a base in the current style.
|
|
*/
|
|
sup(): Style {
|
|
return styles[sup[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Get the style of a subscript given a base in the current style.
|
|
*/
|
|
sub(): Style {
|
|
return styles[sub[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Get the style of a fraction numerator given the fraction in the current
|
|
* style.
|
|
*/
|
|
fracNum(): Style {
|
|
return styles[fracNum[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Get the style of a fraction denominator given the fraction in the current
|
|
* style.
|
|
*/
|
|
fracDen(): Style {
|
|
return styles[fracDen[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Get the cramped version of a style (in particular, cramping a cramped style
|
|
* doesn't change the style).
|
|
*/
|
|
cramp(): Style {
|
|
return styles[cramp[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Get a text or display version of this style.
|
|
*/
|
|
text(): Style {
|
|
return styles[text[this.id]];
|
|
}
|
|
|
|
/**
|
|
* Return true if this style is tightly spaced (scriptstyle/scriptscriptstyle)
|
|
*/
|
|
isTight(): boolean {
|
|
return this.size >= 2;
|
|
}
|
|
}
|
|
|
|
// Export an interface for type checking, but don't expose the implementation.
|
|
// This way, no more styles can be generated.
|
|
export interface StyleInterface {
|
|
id: number;
|
|
size: number;
|
|
cramped: boolean;
|
|
|
|
sup(): StyleInterface;
|
|
sub(): StyleInterface;
|
|
fracNum(): StyleInterface;
|
|
fracDen(): StyleInterface;
|
|
cramp(): StyleInterface;
|
|
text(): StyleInterface;
|
|
isTight(): boolean;
|
|
}
|
|
|
|
// IDs of the different styles
|
|
const D = 0;
|
|
const Dc = 1;
|
|
const T = 2;
|
|
const Tc = 3;
|
|
const S = 4;
|
|
const Sc = 5;
|
|
const SS = 6;
|
|
const SSc = 7;
|
|
|
|
// Instances of the different styles
|
|
const styles = [
|
|
new Style(D, 0, false),
|
|
new Style(Dc, 0, true),
|
|
new Style(T, 1, false),
|
|
new Style(Tc, 1, true),
|
|
new Style(S, 2, false),
|
|
new Style(Sc, 2, true),
|
|
new Style(SS, 3, false),
|
|
new Style(SSc, 3, true),
|
|
];
|
|
|
|
// Lookup tables for switching from one style to another
|
|
const sup = [S, Sc, S, Sc, SS, SSc, SS, SSc];
|
|
const sub = [Sc, Sc, Sc, Sc, SSc, SSc, SSc, SSc];
|
|
const fracNum = [T, Tc, S, Sc, SS, SSc, SS, SSc];
|
|
const fracDen = [Tc, Tc, Sc, Sc, SSc, SSc, SSc, SSc];
|
|
const cramp = [Dc, Dc, Tc, Tc, Sc, Sc, SSc, SSc];
|
|
const text = [D, Dc, T, Tc, T, Tc, T, Tc];
|
|
|
|
// We only export some of the styles.
|
|
export default {
|
|
DISPLAY: (styles[D]: Style),
|
|
TEXT: (styles[T]: Style),
|
|
SCRIPT: (styles[S]: Style),
|
|
SCRIPTSCRIPT: (styles[SS]: Style),
|
|
};
|