1 package net.mograsim.logic.core.types;
3 import java.util.Arrays;
5 import java.util.Objects;
8 * stdlogic according to IEEE 1164
10 public enum Bit implements StrictLogicType<Bit>
12 U("U"), X("X"), ZERO("0"), ONE("1"), Z("Z");
14 private final String symbol;
16 private Bit(String symbol)
22 * Returns if the Bit is binary, this is only true for <code>ZERO</code> and <code>ONE</code>.
24 * @return true if and only if <code>this == ONE || this == ZERO</code>
26 public boolean isBinary()
28 return this == ONE || this == ZERO;
32 public Bit and(Bit other)
34 return fromTable(AND_TABLE, this, other);
38 public Bit or(Bit other)
40 return fromTable(OR_TABLE, this, other);
44 public Bit xor(Bit other)
46 return fromTable(XOR_TABLE, this, other);
65 public Bit[] makeArray(int length)
67 Bit[] bits = new Bit[length];
68 Arrays.fill(bits, this);
72 public BitVector toVector(int length)
74 return BitVector.of(this, length);
78 public Bit join(Bit other)
80 return fromTable(JOIN_TABLE, this, other);
84 public String toString()
89 public String getSymbol()
94 public static Bit lastBitOf(int value)
96 return values()[2 + (value & 1)];
99 public static Bit of(boolean binaryValue)
101 return binaryValue ? ONE : ZERO;
104 public static Bit parse(String s)
106 Bit bit = SYMBOL_MAP.get(s);
107 Objects.requireNonNull(bit, "No Bit found for symbol " + s);
111 public static Bit parse(String s, int symbolPosition)
113 return parse(s.substring(symbolPosition, symbolPosition + 1));
116 private static Bit fromTable(Bit[][] table, Bit a, Bit b)
118 return table[a.ordinal()][b.ordinal()];
121 static final Map<String, Bit> SYMBOL_MAP = Map.of(U.symbol, U, X.symbol, X, ZERO.symbol, ZERO, ONE.symbol, ONE, Z.symbol, Z);
124 private static final Bit[][] JOIN_TABLE =
127 { U, X, ZERO, X, ZERO },
128 { U, X, X, ONE, ONE },
129 { U, X, ZERO, ONE, Z } };
131 private static final Bit[][] AND_TABLE =
132 { { U, U, ZERO, U, U },
133 { U, X, ZERO, X, X },
134 { ZERO, ZERO, ZERO, ZERO, ZERO },
135 { U, X, ZERO, ONE, X },
136 { U, X, ZERO, X, X } };
138 private static final Bit[][] OR_TABLE =
139 { { U, U, U, ONE, U },
141 { U, X, ZERO, ONE, X },
142 { ONE, ONE, ONE, ONE, ONE },
143 { U, X, X, ONE, X } };
145 private static final Bit[][] XOR_TABLE =
148 { U, X, ZERO, ONE, X },
149 { U, X, ONE, ZERO, X },