Handle covert leaves differently, add "PRO", remove "v0"

src/boxes.ts

@@ -46,7 +46,7 @@ function skipFree(tree: Tree): Tree {
 
 function words(tree: Tree): string {
 	if ('word' in tree) {
-		if (tree.word === 'covert' || tree.word === 'functional') {
+		if (tree.word === 'covert') {
 			return '';
 		} else {
 			return tree.word.text;
@@ -91,7 +91,7 @@ function boxifyClause(tree: Tree): BoxClause {
 	if (!('left' in cp)) throw new Error('bad CP?');
 	const c = cp.left;
 	if (!('word' in c)) throw new Error('C without word?');
-	if (c.word !== 'covert' && c.word !== 'functional') {
+	if (c.word !== 'covert') {
 		complementizer = c.word.text;
 	}
 	for (let node = cp.right; ; ) {
@@ -149,7 +149,7 @@ export function boxify(tree: Tree): BoxSentence {
 	const sa = tree.right;
 	if (sa.label !== 'SA') throw new Error('SAP without SA?');
 	if (!('word' in sa)) throw new Error('SA without word?');
-	if (sa.word !== 'covert' && sa.word !== 'functional') {
+	if (sa.word !== 'covert') {
 		speechAct = sa.word.text;
 	}
 	const cp = tree.left;

src/draw-tree.ts

@@ -53,12 +53,7 @@ export function placeLeaf(
 	const gloss =
 		typeof leaf.word === 'string' ? undefined : leaf.word.entry?.gloss;
 	const label = getLabel(leaf);
-	const word =
-		leaf.word === 'functional'
-			? undefined
-			: leaf.word === 'covert'
-			? '∅'
-			: leaf.word.text;
+	const word = leaf.word === 'covert' ? leaf.value : leaf.word.text;
 	const denotation =
 		'denotation' in leaf && leaf.denotation !== null
 			? toPlainText(leaf.denotation)

src/english.ts

@@ -14,7 +14,6 @@ function leafText(tree: Tree): string {
 		throw new Error('Unexpected non-leaf ' + tree.label);
 	}
 	if (tree.word === 'covert') return '';
-	if (tree.word === 'functional') return '';
 	return tree.word.text;
 }
 
@@ -364,7 +363,7 @@ function branchToEnglish(tree: Branch<Tree>): Constituent {
 			{ she: 'necessarily', ao: 'would', daı: 'possibly', ea: 'could' }[
 				bare(leafText(modal))
 			] ?? '?';
-		if (c.word === 'covert' || c.word === 'functional') {
+		if (c.word === 'covert') {
 			return { text: eng };
 		} else {
 			return {

src/grammar.ts

@@ -45,7 +45,6 @@ const {
 	makeAdjunctPT,
 	makeBranch,
 	makeBranchCovertLeft,
-	makeBranchFunctionalLeft,
 	makeConn,
     makeCovertLeaf,
 	makeLeaf,
@@ -110,7 +109,7 @@ const grammar: Grammar = {
     {"name": "DP", "symbols": ["D", "nP"], "postprocess": makeBranch('DP')},
     {"name": "DP", "symbols": ["Focus", "DP"], "postprocess": makeBranch('FocusP')},
     {"name": "nP", "symbols": ["nP", "CPrel"], "postprocess": makeBranch('nP')},
-    {"name": "nP", "symbols": ["CPdet"], "postprocess": makeBranchFunctionalLeft('nP', 'n')},
+    {"name": "nP", "symbols": ["CPdet"], "postprocess": makeBranchCovertLeft('nP', 'n')},
     {"name": "Clause", "symbols": ["term", "Bi", "Clause"], "postprocess": make3L('TopicP', "Topic'")},
     {"name": "Clause", "symbols": ["MTP"], "postprocess": id},
     {"name": "Clause", "symbols": ["DP", "Na", "CPrelna"], "postprocess": make3L('𝘷P', "𝘷'")},

src/latex.ts

@@ -26,9 +26,6 @@ export function toLatex(tree: Tree | DTree): string {
 		const children = tree.children.map(toLatex).join(' ');
 		return `[${label} ${children}]`;
 	} else {
-		if (tree.word === 'functional') {
-			return `[${label}]`;
-		}
 		if (tree.word === 'covert') {
 			return `[${label} [$\\varnothing$]]`;
 		}

src/semantics/denote.ts

@@ -351,10 +351,12 @@ const littleVAgent = λ('e', ['s'], c =>
 // λ𝘗. 𝘗
 const na = λ(['e', 't'], [], c => v(0, c));
 
-function denoteLittleV(toaq: string | null): Expr {
+function denoteLittleV(toaq: string | null): Expr | null {
 	switch (toaq) {
-		case null:
+		case 'CAUSE':
 			return littleVAgent;
+		case 'BE':
+			return null;
 		case 'nä':
 			return na;
 		default:
@@ -415,9 +417,7 @@ function denoteLeaf(leaf: Leaf, cCommand: StrictTree | null): DTree {
 
 		denotation = denoteVerb(entry.toaq, entry.frame.split(' ').length);
 	} else if (leaf.label === 'DP') {
-		if (leaf.word === 'functional') {
-			throw new Error('Functional DP');
-		} else if (leaf.word === 'covert') {
+		if (leaf.word === 'covert') {
 			denotation = hoa;
 			bindings = covertHoaBindings;
 		} else if (leaf.word.entry === undefined) {
@@ -518,22 +518,17 @@ function denoteLeaf(leaf: Leaf, cCommand: StrictTree | null): DTree {
 		};
 	} else if (leaf.label === '𝘷') {
 		let toaq: string | null;
-		if (typeof leaf.word === 'string') {
-			toaq = null;
+		if (leaf.word === 'covert') {
+			toaq = leaf.value;
 		} else if (leaf.word.entry === undefined) {
 			throw new Error(`Unrecognized 𝘷: ${leaf.word.text}`);
 		} else {
 			toaq = leaf.word.entry.toaq;
 		}
-
 		denotation = denoteLittleV(toaq);
-	} else if (leaf.label === '𝘷0') {
-		denotation = null;
 	} else if (leaf.label === 'Asp') {
 		let toaq: string;
-		if (leaf.word === 'functional') {
-			throw new Error('Functional Asp');
-		} else if (leaf.word === 'covert') {
+		if (leaf.word === 'covert') {
 			toaq = 'tam';
 		} else if (leaf.word.entry === undefined) {
 			throw new Error(`Unrecognized Asp: ${leaf.word.text}`);
@@ -543,9 +538,7 @@ function denoteLeaf(leaf: Leaf, cCommand: StrictTree | null): DTree {
 
 		denotation = denoteAspect(toaq);
 	} else if (leaf.label === 'T') {
-		if (leaf.word === 'functional') {
-			throw new Error('Functional T');
-		} else if (leaf.word === 'covert') {
+		if (leaf.word === 'covert') {
 			denotation = defaultTense;
 		} else if (leaf.word.entry === undefined) {
 			throw new Error(`Unrecognized T: ${leaf.word.text}`);
@@ -556,9 +549,7 @@ function denoteLeaf(leaf: Leaf, cCommand: StrictTree | null): DTree {
 		denotation = null;
 	} else if (leaf.label === 'SA') {
 		let toaq: string;
-		if (leaf.word === 'functional') {
-			throw new Error('Functional SA');
-		} else if (leaf.word === 'covert') {
+		if (leaf.word === 'covert') {
 			toaq = 'da'; // TODO: covert móq
 		} else if (leaf.word.entry === undefined) {
 			throw new Error(`Unrecognized SA: ${leaf.word.text}`);
@@ -771,7 +762,6 @@ function getCompositionRule(left: DTree, right: DTree): CompositionRule {
 	switch (left.label) {
 		case 'V':
 		case 'Asp':
-		case '𝘷0':
 		case 'n':
 			return functionalApplication;
 		case 'T':

src/serial.ts

@@ -2,12 +2,11 @@ import { Branch, Label, Tree } from './tree';
 
 const arityPreservingVerbPrefixes: Label[] = ['buP', 'muP', 'buqP', 'geP'];
 
-const pro: Tree = { label: 'DP', word: 'covert' };
+const pro: Tree = { label: 'DP', word: 'covert', value: 'PRO' };
 
 export function getFrame(verb: Tree): string {
 	if ('word' in verb) {
 		if (verb.word === 'covert') throw new Error('covert verb?');
-		if (verb.word === 'functional') throw new Error('functional verb?');
 		if (verb.word.entry?.type === 'predicate') {
 			return verb.word.entry.frame;
 		} else {
@@ -42,7 +41,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 		if (arity === 1) {
 			return {
 				label: '𝘷P',
-				left: { label: '𝘷0', word: 'functional' },
+				left: { label: '𝘷', word: 'covert', value: 'BE' },
 				right: { label: 'VP', left: verbs[0], right: args[0] },
 			};
 		} else if (arity === 2) {
@@ -51,7 +50,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 				left: args[0],
 				right: {
 					label: "𝘷'",
-					left: { label: '𝘷', word: 'functional' },
+					left: { label: '𝘷', word: 'covert', value: 'CAUSE' },
 					right: { label: 'VP', left: verbs[0], right: args[1] },
 				},
 			};
@@ -61,7 +60,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 				left: args[0],
 				right: {
 					label: "𝘷'",
-					left: { label: '𝘷', word: 'functional' },
+					left: { label: '𝘷', word: 'covert', value: 'CAUSE' },
 					right: {
 						label: 'VP',
 						left: args[1],
@@ -95,7 +94,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 		if (arity === 1) {
 			return {
 				label: '𝘷P',
-				left: { label: '𝘷0', word: 'functional' },
+				left: { label: '𝘷', word: 'covert', value: 'BE' },
 				right: { label: 'VP', left: verbs[0], right: inner },
 			};
 		} else if (arity === 2) {
@@ -104,7 +103,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 				left: args[0],
 				right: {
 					label: "𝘷'",
-					left: { label: '𝘷', word: 'functional' },
+					left: { label: '𝘷', word: 'covert', value: 'CAUSE' },
 					right: { label: 'VP', left: verbs[0], right: inner },
 				},
 			};
@@ -114,7 +113,7 @@ function serialTovP(verbs: Tree[], args: Tree[]): Tree {
 				left: args[0],
 				right: {
 					label: "𝘷'",
-					left: { label: '𝘷', word: 'functional' },
+					left: { label: '𝘷', word: 'covert', value: 'CAUSE' },
 					right: {
 						label: 'VP',
 						left: args[1],
@@ -137,18 +136,19 @@ function attachAdjective(VP: Tree, vP: Tree): Tree {
 			left: {
 				label: 'a',
 				word: 'covert', // TODO ki
+				value: '∅',
 			},
 			right: {
 				// TODO: oh god, adjectives can have T and Asp?
 				// needs rework in nearley grammar
 				label: 'CPrel',
-				left: { label: 'C', word: 'covert' },
+				left: { label: 'C', word: 'covert', value: '∅' },
 				right: {
 					label: 'TP',
-					left: { label: 'T', word: 'covert' },
+					left: { label: 'T', word: 'covert', value: '∅' },
 					right: {
 						label: 'AspP',
-						left: { label: 'Asp', word: 'covert' },
+						left: { label: 'Asp', word: 'covert', value: '∅' },
 						right: vP,
 					},
 				},

src/textual-tree.ts

@@ -3,11 +3,7 @@ import { Tree } from './tree';
 function ttree_converted(data: Tree): { label: string; branches: any } {
 	if ('word' in data) {
 		const b =
-			data.word === 'covert'
-				? '∅'
-				: data.word === 'functional'
-				? '🅵'
-				: data.word.text.toLowerCase();
+			data.word === 'covert' ? data.value : data.word.text.toLowerCase();
 		return { label: data.label, branches: [b] };
 	} else if ('left' in data) {
 		return {

src/toaq.ne

@@ -8,7 +8,6 @@ const {
 	makeAdjunctPT,
 	makeBranch,
 	makeBranchCovertLeft,
-	makeBranchFunctionalLeft,
 	makeConn,
     makeCovertLeaf,
 	makeLeaf,
@@ -61,7 +60,7 @@ DP -> Focus DP {% makeBranch('FocusP') %}
 # (sá) ꝡë hao
 nP -> nP CPrel {% makeBranch('nP') %}
 # (sá) ∅ hao
-nP -> CPdet {% makeBranchFunctionalLeft('nP', 'n') %}
+nP -> CPdet {% makeBranchCovertLeft('nP', 'n') %}
 
 # ní bï pu hao
 Clause -> term Bi Clause {% make3L('TopicP', "Topic'") %}

src/tree.ts

@@ -62,7 +62,6 @@ export type Label =
 	| "Topic'"
 	| 'TopicP'
 	| '𝘷'
-	| '𝘷0'
 	| "𝘷'"
 	| 'V'
 	| "V'"
@@ -87,11 +86,7 @@ export function containsWords(
 	stopLabels: Label[],
 ): boolean {
 	if ('word' in tree) {
-		return (
-			tree.word !== 'covert' &&
-			tree.word !== 'functional' &&
-			words.includes(clean(tree.word.text))
-		);
+		return tree.word !== 'covert' && words.includes(clean(tree.word.text));
 	} else if ('left' in tree) {
 		return (
 			(!stopLabels.includes(tree.left.label) &&
@@ -116,13 +111,25 @@ export function isQuestion(tree: Tree): boolean {
 	);
 }
 
-export interface Leaf {
+export interface OvertLeaf {
 	label: Label;
 	id?: string;
 	movedTo?: string;
-	word: Word | 'covert' | 'functional';
+	word: Word;
 }
 
+type CovertValue = '∅' | 'BE' | 'CAUSE' | 'PRO';
+
+export interface CovertLeaf {
+	label: Label;
+	id?: string;
+	movedTo?: string;
+	word: 'covert';
+	value: CovertValue;
+}
+
+export type Leaf = OvertLeaf | CovertLeaf;
+
 export interface Branch<T> {
 	label: Label;
 	left: T;
@@ -189,16 +196,6 @@ export function makeBranch(label: Label) {
 	};
 }
 
-export function makeBranchFunctionalLeft(label: Label, functionalLabel: Label) {
-	return ([right]: [Tree, Tree]) => {
-		return {
-			label,
-			left: { label: functionalLabel, word: 'functional' },
-			right,
-		};
-	};
-}
-
 export function makeBranchCovertLeft(label: Label, covertLabel: Label) {
 	return ([right]: [Tree, Tree]) => {
 		return {
@@ -366,7 +363,7 @@ export function makeT1ModalvP([modal, tp]: [Tree, Tree]) {
 			label: "𝘷'",
 			left: {
 				label: '𝘷',
-				word: 'functional',
+				word: 'covert',
 			},
 			right: tp,
 		},