add initial marp implementation with sample content and build configuration

node_modules/mathjax-full/ts/input/tex/cases/CasesConfiguration.ts

@@ -0,0 +1,212 @@
+import {Configuration} from '../Configuration.js';
+import {EnvironmentMap, MacroMap} from '../SymbolMap.js';
+import ParseUtil from '../ParseUtil.js';
+import BaseMethods from '../base/BaseMethods.js';
+import TexParser from '../TexParser.js';
+import TexError from '../TexError.js';
+import {BeginItem, EqnArrayItem} from '../base/BaseItems.js';
+import {AmsTags} from '../ams/AmsConfiguration.js';
+import {StackItem, CheckType} from '../StackItem.js';
+import {MmlMtable} from '../../../core/MmlTree/MmlNodes/mtable.js';
+import {EmpheqUtil} from '../empheq/EmpheqUtil.js';
+
+/**
+ * The StackItem for the numcases environment.
+ */
+export class CasesBeginItem extends BeginItem {
+
+  /**
+   * @override
+   */
+  get kind() {
+    return 'cases-begin';
+  }
+
+  /**
+   * @override
+   */
+  public checkItem(item: StackItem) {
+    if (item.isKind('end') && item.getName() === this.getName()) {
+      if (this.getProperty('end')) {
+        this.setProperty('end', false);
+        return [[], true] as CheckType;
+      }
+    }
+    return super.checkItem(item);
+  }
+
+}
+
+/**
+ * A tagging class for the subnumcases environment.
+ */
+export class CasesTags extends AmsTags {
+
+  /**
+   * The counter for the subnumber.
+   */
+  protected subcounter = 0;
+
+  /**
+   * @override
+   */
+  public start(env: string, taggable: boolean, defaultTags: boolean) {
+    this.subcounter = 0;
+    super.start(env, taggable, defaultTags);
+  }
+
+  /**
+   * @override
+   */
+  public autoTag() {
+    if (this.currentTag.tag != null) return;
+    if (this.currentTag.env === 'subnumcases') {
+      if (this.subcounter === 0) this.counter++;
+      this.subcounter++;
+      this.tag(this.formatNumber(this.counter, this.subcounter), false);
+    } else {
+      if (this.subcounter === 0 || this.currentTag.env !== 'numcases-left') this.counter++;
+      this.tag(this.formatNumber(this.counter), false);
+    }
+  }
+
+  /**
+   * @override
+   */
+  public formatNumber(n: number, m: number = null) {
+    return n.toString() + (m === null ? '' : String.fromCharCode(0x60 + m));
+  }
+
+}
+
+export const CasesMethods = {
+
+  /**
+   * Implements the numcases environment.
+   *
+   * @param {TexParser} texparser   The active tex parser.
+   * @param {CasesBeginItem} begin  The environment begin item.
+   */
+  NumCases(parser: TexParser, begin: CasesBeginItem) {
+    if (parser.stack.env.closing === begin.getName()) {
+      delete parser.stack.env.closing;
+      parser.Push(parser.itemFactory.create('end').setProperty('name', begin.getName())); // finish eqnarray
+      const cases = parser.stack.Top();
+      const table = cases.Last as MmlMtable;
+      const original = ParseUtil.copyNode(table, parser) as MmlMtable;
+      const left = cases.getProperty('left');
+      EmpheqUtil.left(table, original, left + '\\empheqlbrace\\,', parser, 'numcases-left');
+      parser.Push(parser.itemFactory.create('end').setProperty('name', begin.getName()));
+      return null;
+    } else {
+      const left = parser.GetArgument('\\begin{' + begin.getName() + '}');
+      begin.setProperty('left', left);
+      const array = BaseMethods.EqnArray(parser, begin, true, true, 'll', ) as EqnArrayItem;
+      array.arraydef.displaystyle = false;
+      array.arraydef.rowspacing = '.2em';
+      array.setProperty('numCases', true);
+      parser.Push(begin);
+      return array;
+    }
+  },
+
+  /**
+   * Replacement for & in cases environment.
+   */
+  Entry(parser: TexParser, name: string) {
+    if (!parser.stack.Top().getProperty('numCases')) {
+      return BaseMethods.Entry(parser, name);
+    }
+    parser.Push(parser.itemFactory.create('cell').setProperties({isEntry: true, name: name}));
+    //
+    //  Make second column be in \text{...}
+    //
+    const tex = parser.string;
+    let braces = 0, i = parser.i, m = tex.length;
+    //
+    //  Look through the string character by character...
+    //
+    while (i < m) {
+      const c = tex.charAt(i);
+      if (c === '{') {
+        //
+        //  Increase the nested brace count and go on
+        //
+        braces++;
+        i++;
+      } else if (c === '}') {
+        //
+        //  If there are too many close braces, just end (we will get an
+        //    error message later when the rest of the string is parsed)
+        //  Otherwise
+        //    decrease the nested brace count,
+        //    go on to the next character.
+        //
+        if (braces === 0) {
+          break;
+        } else {
+          braces--;
+          i++;
+        }
+      } else if (c === '&' && braces === 0) {
+        //
+        //  Extra alignment tabs are not allowed in cases
+        //
+        throw new TexError('ExtraCasesAlignTab', 'Extra alignment tab in text for numcase environment');
+      } else if (c === '\\' && braces === 0) {
+        //
+        //  If the macro is \cr or \\, end the search, otherwise skip the macro
+        //  (multi-letter names don't matter, as we will skip the rest of the
+        //   characters in the main loop)
+        //
+        const cs = (tex.slice(i + 1).match(/^[a-z]+|./i) || [])[0];
+        if (cs === '\\' || cs === 'cr' || cs === 'end' || cs === 'label') {
+          break;
+        } else {
+          i += cs.length;
+        }
+      } else {
+        //
+        //  Go on to the next character
+        //
+        i++;
+      }
+    }
+    //
+    //  Process the second column as text and continue parsing from there,
+    //
+    const text = tex.substr(parser.i, i - parser.i).replace(/^\s*/, '');
+    parser.PushAll(ParseUtil.internalMath(parser, text, 0));
+    parser.i = i;
+  }
+
+};
+
+/**
+ * The environments for this package
+ */
+new EnvironmentMap('cases-env', EmpheqUtil.environment, {
+  numcases: ['NumCases', 'cases'],
+  subnumcases: ['NumCases', 'cases']
+}, CasesMethods);
+
+/**
+ * The macros for this package
+ */
+new MacroMap('cases-macros', {
+  '&': 'Entry'
+}, CasesMethods);
+
+//
+//  Define the package for our new environment
+//
+export const CasesConfiguration = Configuration.create('cases', {
+  handler: {
+    environment: ['cases-env'],
+    character: ['cases-macros']
+  },
+  items: {
+    [CasesBeginItem.prototype.kind]: CasesBeginItem
+  },
+  tags: {'cases': CasesTags}
+});