ExDiceRoller v1.0.0-rc.2 ExDiceRoller.Parser View Source

Functionality for parsing ExDiceRoller.Tokenizer.tokens/0.

iex> {:ok, tokens} = ExDiceRoller.Tokenizer.tokenize("2d3+9-(ydz)d(31+x)/(3d8+2)")
{:ok,
[
  {:int, 1, '2'},
  {:roll, 1, 'd'},
  {:int, 1, '3'},
  {:basic_operator, 1, '+'},
  {:int, 1, '9'},
  {:basic_operator, 1, '-'},
  {:"(", 1, '('},
  {:var, 1, 'y'},
  {:roll, 1, 'd'},
  {:var, 1, 'z'},
  {:")", 1, ')'},
  {:roll, 1, 'd'},
  {:"(", 1, '('},
  {:int, 1, '31'},
  {:basic_operator, 1, '+'},
  {:var, 1, 'x'},
  {:")", 1, ')'},
  {:complex_operator, 1, '/'},
  {:"(", 1, '('},
  {:int, 1, '3'},
  {:roll, 1, 'd'},
  {:int, 1, '8'},
  {:basic_operator, 1, '+'},
  {:int, 1, '2'},
  {:")", 1, ')'}
]}
iex> ExDiceRoller.Parser.parse(tokens)
{:ok,
{{:operator, '-'},
  {{:operator, '+'}, {:roll, 2, 3}, 9},
  {{:operator, '/'},
  {:roll, {:roll, {:var, 'y'}, {:var, 'z'}},
    {{:operator, '+'}, 31, {:var, 'x'}}},
  {{:operator, '+'}, {:roll, 3, 8}, 2}}}}

Link to this section Summary

Converts a series of tokens provided by tokenize/1 and parses them into an expression structure. This expression structure is what’s used by the dice rolling functions to calculate rolls. The BNF grammar definition file is located at src/dice_parser.yrl

Link to this section Types

expression()

expression() ::
  number()
  | {{:operator, charlist()}, expression(), expression()}
  | {:roll, expression(), expression()}
  | {:var, charlist()}
  | {:sep, expression(), expression()}

Link to this section Functions

parse(tokens)

parse(ExDiceRoller.Tokenizer.tokens()) :: {:ok, expression()}

iex> {:ok, tokens} = ExDiceRoller.tokenize("2d8 + (1+2)")
{:ok,
[
  {:int, 1, '2'},
  {:roll, 1, 'd'},
  {:int, 1, '8'},
  {:basic_operator, 1, '+'},
  {:"(", 1, '('},
  {:int, 1, '1'},
  {:basic_operator, 1, '+'},
  {:int, 1, '2'},
  {:")", 1, ')'}
]}
iex> {:ok, _} = ExDiceRoller.parse(tokens)
{:ok,
{{:operator, '+'}, {:roll, 2, 8},
  {{:operator, '+'}, 1, 2}}}