Ergo.Context.next_char

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next_char(context)

Reads the next character from the input of the passed in Context.

If the input is empty returns status: {:error, :unexpected_eoi}.

Otherwise returns a new Context setting char to the character read and incrementing positional variables such as index, line, and column appropriately.

Examples

iex> Context.next_char(Context.new()) %Context{status: {:error, :unexpected_eoi}, message: "Unexpected end of input"}

iex> Context.next_char(Context.new("Hello World")) %Context{status: :ok, input: "ello World", char: ?H, ast: ?H, index: 1, line: 1, col: 2}