26 lines
685 B
Elixir
26 lines
685 B
Elixir
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defmodule RPNCalculator.Exception do
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defmodule DivisionByZeroError do
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defexception message: "division by zero occurred"
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end
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defmodule StackUnderflowError do
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defexception message: "stack underflow occurred"
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@impl true
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def exception(value) do
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case value do
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[] ->
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%StackUnderflowError{}
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_ ->
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%StackUnderflowError{message: "stack underflow occurred, context: " <> value}
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end
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end
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end
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def divide([]), do: raise(StackUnderflowError, "when dividing")
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def divide([_]), do: raise(StackUnderflowError, "when dividing")
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def divide([0, _]), do: raise(DivisionByZeroError)
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def divide([x, y]), do: div(y, x)
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end
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