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%% Copyright (c) 2023 Peter Morgan <peter.james.morgan@gmail.com> |
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%% |
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%% Licensed under the Apache License, Version 2.0 (the "License"); |
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%% you may not use this file except in compliance with the License. |
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%% You may obtain a copy of the License at |
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%% |
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%% http://www.apache.org/licenses/LICENSE-2.0 |
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%% |
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%% Unless required by applicable law or agreed to in writing, software |
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%% distributed under the License is distributed on an "AS IS" BASIS, |
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%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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%% See the License for the specific language governing permissions and |
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%% limitations under the License. |
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%% @doc Encoder combinators for bit output. |
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-module(narcs_bits). |
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-export([into_bit/0]). |
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-export([into_bit/1]). |
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-export([into_bitfield/1]). |
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%% @doc Given a map of flags, output a bitstring ordered using the |
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%% supplied names. |
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-spec into_bitfield(#{A => boolean()}) -> narcs:encoder([A], bitstring()). |
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into_bitfield(Flags) -> |
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fun |
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(Names) -> |
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list_to_bitstring( |
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lists:map( |
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fun |
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(Name) -> |
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(into_bit())(maps:get(Name, Flags, false)) |
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end, |
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Names)) |
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end. |
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%% @doc Output a bit from a boolean value. |
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-spec into_bit() -> narcs:encoder(boolean(), <<_:1>>). |
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into_bit() -> |
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fun |
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(true) -> |
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<<1:1>>; |
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(false) -> |
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<<0:1>> |
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end. |
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-spec into_bit(narcs:encoder(A, boolean())) -> narcs:encoder(A, <<_:1>>). |
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into_bit(Encoder) -> |
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:-( |
fun |
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(Decoded) -> |
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:-( |
(into_bit())(Encoder(Decoded)) |
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end. |