bool.h

Boolean algebra.

Defines

ML99_true(...)

Truth.

ML99_false(...)

Falsehood.

ML99_not(x)

Logical negation.

Examples

#include <metalang99/bool.h>

// 1
ML99_not(v(0))

// 0
ML99_not(v(1))

ML99_and(x, y)

Logical conjunction.

Examples

#include <metalang99/bool.h>

// 0
ML99_and(v(0), v(0))

// 0
ML99_and(v(0), v(1))

// 0
ML99_and(v(1), v(0))

// 1
ML99_and(v(1), v(1))

ML99_or(x, y)

Logical inclusive OR.

Examples

#include <metalang99/bool.h>

// 0
ML99_or(v(0), v(0))

// 1
ML99_or(v(0), v(1))

// 1
ML99_or(v(1), v(0))

// 1
ML99_or(v(1), v(1))

ML99_xor(x, y)

Logical exclusive OR.

Examples

#include <metalang99/bool.h>

// 0
ML99_xor(v(0), v(0))

// 1
ML99_xor(v(0), v(1))

// 1
ML99_xor(v(1), v(0))

// 0
ML99_xor(v(1), v(1))

ML99_boolEq(x, y)

Tests x and y for equality.

Examples

#include <metalang99/bool.h>

// 1
ML99_boolEq(v(0), v(0))

// 0
ML99_boolEq(v(0), v(1))

// 0
ML99_boolEq(v(1), v(0))

// 1
ML99_boolEq(v(1), v(1))

ML99_boolMatch(x, matcher)

Matches x against the two cases: if it is 0 or 1.

Examples

#include <metalang99/bool.h>

#define MATCH_1_IMPL() v(Billie)
#define MATCH_0_IMPL() v(Jean)

// Billie
ML99_boolMatch(v(1), v(MATCH_))

// Jean
ML99_boolMatch(v(0), v(MATCH_))

Note

This function calls f with ML99_call, so no partial application occurs, and so arity specifiers are not needed.

ML99_boolMatchWithArgs(x, matcher, ...)

The same as ML99_boolMatch but provides additional arguments to all branches.

Examples

#include <metalang99/bool.h>

#define MATCH_1_IMPL(x, y, z) v(Billie ~ x y z)
#define MATCH_0_IMPL(x, y, z) v(Jean ~ x y z)

// Billie ~ 1 2 3
ML99_boolMatchWithArgs(v(1), v(MATCH_), v(1, 2, 3))

// Jean ~ 1 2 3
ML99_boolMatchWithArgs(v(0), v(MATCH_), v(1, 2, 3))

ML99_if(cond, x, y)

If cond is true, evaluates to x, otherwise y.

Examples

#include <metalang99/bool.h>

// 123
ML99_if(v(1), v(123), v(18))

// 18
ML99_if(v(0), v(123), v(18))

ML99_IF(cond, x, y)

The plain version of ML99_if.

This macro can imitate lazy evaluation: ML99_IF(<cond>, <term>, <another-term>) will expand to one of the two terms, which can be evaluated further; if <cond> is 0, then <term> will not be evaluated, and the same with <another-term>.

Note

x and y can possibly expand to commas. It means that you can supply ML99_TERMS(...) as a branch, for example.

ML99_TRUE(...)
ML99_FALSE(...)
ML99_NOT(x)
ML99_AND(x, y)
ML99_OR(x, y)
ML99_XOR(x, y)
ML99_BOOL_EQ(x, y)