diff options
| -rw-r--r-- | __tests__/lexer.test.js | 12 | ||||
| -rw-r--r-- | __tests__/parser.test.js | 12 | ||||
| -rw-r--r-- | index.js | 2 | ||||
| -rw-r--r-- | src/lexer.js | 1 | ||||
| -rw-r--r-- | src/parser.js | 14 |
5 files changed, 41 insertions, 0 deletions
diff --git a/__tests__/lexer.test.js b/__tests__/lexer.test.js index 3003fb9..04a95e1 100644 --- a/__tests__/lexer.test.js +++ b/__tests__/lexer.test.js @@ -136,4 +136,16 @@ describe('lex', () => { ]) }) }) + + describe('keep', () => { + test('1K2d20', () => { + expect(lex('1K2d20')).toEqual([ + { type: 'constant', value: 1 }, + { type: 'K' }, + { type: 'constant', value: 2 }, + { type: 'd' }, + { type: 'constant', value: 20 } + ]) + }) + }) }) diff --git a/__tests__/parser.test.js b/__tests__/parser.test.js index 26febef..fb554f9 100644 --- a/__tests__/parser.test.js +++ b/__tests__/parser.test.js @@ -127,6 +127,18 @@ describe('parse', () => { }) }) + it('parses dice with keep', () => { + expect(parse('1K2d20')).toEqual({ + type: 'K', + left: { type: 'constant', value: 1 }, + right: { + type: 'd', + left: { type: 'constant', value: 2 }, + right: { type: 'constant', value: 20 } + } + }) + }) + describe('parsing parentheses', () => { test('(1d6)d6', () => { expect(parse('(1d6)d6')).toEqual({ @@ -9,6 +9,8 @@ const interpret = tree => { return D.d(interpret(tree.left), interpret(tree.right)) case 'E': return D.explode(interpret(tree.left), interpret(tree.right)) + case 'K': + return D.keepHigh(interpret(tree.left), interpret(tree.right)) case 'add': return D.add(interpret(tree.left), interpret(tree.right)) case 'subtract': diff --git a/src/lexer.js b/src/lexer.js index 85579fb..fd0d0a3 100644 --- a/src/lexer.js +++ b/src/lexer.js @@ -25,6 +25,7 @@ newLexemeType('-', '-') newLexemeType('(', '\\(') newLexemeType(')', '\\)') newLexemeType('E', 'E') +newLexemeType('K', 'K') newSkippableLexeme('whitespace', '\\s+') const lex = (expressionString) => { diff --git a/src/parser.js b/src/parser.js index 9479abc..5e9960a 100644 --- a/src/parser.js +++ b/src/parser.js @@ -6,6 +6,8 @@ let throwSyntaxError = () => { throw new Error('Syntax error: unexpected token') } +const dieBindingPower = 30 + let newSymbol = (type, nud, lbp, led) => { symbols[type] = { type, @@ -33,6 +35,16 @@ newSymbol('(', function(parser) { newSymbol(')') +const newDieOperation = (symbol, nud = null) => { + newSymbol(symbol, nud, dieBindingPower, (left, parser) => { + return { + type: symbol, + left: left, + right: parser.expression(dieBindingPower - 1) + } + }) +} + newSymbol('d', (parser) => { return { type: 'd', @@ -55,6 +67,8 @@ newSymbol('E', null, 30, (left, parser) => { } }) +newDieOperation('K') + newSymbol('+', null, 20, (left, parser) => { return { type: 'add', |