Variable NOTATION_ERROR_CODES`Const`

NOTATION_ERROR_CODES: readonly [
    "UNEXPECTED_CHARACTER",
    "UNEXPECTED_IDENTIFIER",
    "UNEXPECTED_TOKEN",
    "UNEXPECTED_END",
    "EXPECTED_TOKEN",
    "INVALID_DICE_COUNT",
    "INVALID_DICE_SIDES",
    "DICE_LIMIT_EXCEEDED",
    "DIVISION_BY_ZERO",
    "MODULO_BY_ZERO",
    "INVALID_KEEP_DROP_COUNT",
    "INVALID_KEEP_DROP_TARGET",
    "EXPLODE_LIMIT_EXCEEDED",
    "INVALID_EXPLODE_TARGET",
    "REROLL_LIMIT_EXCEEDED",
    "INVALID_REROLL_TARGET",
    "INVALID_SUCCESS_COUNT_TARGET",
    "INVALID_SORT_TARGET",
    "INVALID_CRIT_THRESHOLD_TARGET",
    "INVALID_DIE_BOUND_TARGET",
    "INVALID_THRESHOLD",
    "NESTED_VERSUS",
    "INVALID_FUNCTION_ARITY",
    "UNDEFINED_VARIABLE",
    "AMBIGUOUS_DICE_CHAIN",
    "MAX_DEPTH_EXCEEDED",
    "NON_FINITE_RESULT",
    "INVALID_NOTATION_TYPE",
] = ...

The subset of ROLL_PARSER_ERROR_CODES the input is answerable for, as a readonly tuple. Runtime counterpart of NotationErrorCode and the list isNotationError matches against.

A code is in when roll(notation) can raise it for some notation string, given valid options and a valid context — so the right response is to tell whoever supplied the notation that it was rejected. Six codes are out, because for each of them the notation is innocent:

Calling code: INVALID_EVALUATION_LIMIT (a bad maxDice, maxExplodeIterations, or maxRerollIterations), INVALID_VARIABLE_VALUE (a non-finite entry in context), INCOMPATIBLE_RNG_STATE (a snapshot from another version)

Library invariant: UNKNOWN_NODE_TYPE, UNKNOWN_OPERATOR, UNKNOWN_FUNCTION — the lexer and parser only ever hand the evaluator shapes it already covers, so reaching one means a hand-built AST or a bug in here.

Two boundaries are worth knowing. DIVISION_BY_ZERO, MODULO_BY_ZERO, and NON_FINITE_RESULT are in because notation alone reaches them (1d6/0, 10**400), but a context variable reaches them too, so a true is not proof the notation was at fault. INVALID_NOTATION_TYPE is in even though no user can type a non-string: it means the notation you were handed was null or undefined — an absent slash-command option, a missing JSON field — and "give me a dice expression" is the reply that fits.

Example

import { NOTATION_ERROR_CODES } from 'roll-parser';

// Prompt copy is only worth writing for the codes a user can actually cause.
const needsCopy = new Set(NOTATION_ERROR_CODES);

Variable NOTATION_ERROR_CODESConst

Example

Settings

Variable NOTATION_ERROR_CODES`Const`