Experimentally removed Boolean.

Since literals other than integers and floats are now either nulls or objects,
the internal type can be changed from const t_pvalue to t_object*.

doc/Literals.md

@@ -16,7 +16,10 @@ This page explains literals.
 
     boolean: 'true' | 'false' ;
 
-`null` and `false` are falsy. The other values are all truthy.
+xemmai has no boolean type.
+The only falsy value is `null`. The other values are all truthy.
+`true` is an alias for `1.0`, which is float not integer `1` because bitwise operators have to distinguish integer operations and boolean operations.
+`false` is an alias for `null`.
 
 ## Integer Literals
 

doc/ObjectTraits.md

@@ -66,7 +66,6 @@ It can be called only if the object is in the shared state which means no thread
     Method      no         *1
     Throwable   yes        *3
     Null        no         *1
-    Boolean     no         *1
     Integer     yes        *4
     Float       yes        *4
     String      no         *1

doc/StackUsage.md

@@ -104,9 +104,6 @@
     NUL
         |
         |N
-    BOOLEAN
-        |
-        |B
     INTEGER
         |
         |I

doc/TermExpressions.md

@@ -10,7 +10,7 @@ See [PrimaryExpressions](PrimaryExpressions.md).
 
     unary: ('+' | '-' | '!' | '~')* primary ;
 
-Negate operator (`!`) returns `true` if the operand is falsy, returns `false` otherwise.
+Negate operator (`!`) returns `true` (`1.0`) if the operand is `false` (`null`), returns `false` (`null`) otherwise.
 
 ## Multiplicative Expressions
 
@@ -28,7 +28,7 @@ Negate operator (`!`) returns `true` if the operand is falsy, returns `false` ot
 
     relational: shift (('<' | '>' | '<=' | '>=') shift)* ;
 
-Relational, equality, and identity operators return either `true` or `false`.
+Relational, equality, and identity operators return either `true` (`1.0`) or `false` (`null`).
 
 ## Equality Expressions
 
@@ -42,7 +42,7 @@ Relational, equality, and identity operators return either `true` or `false`.
 
     and: identity ('&' identity)* ;
 
-Bitwise operators (`&`, `^`, and `|`) do bitwise operations if both the operands are integers, do boolean operations if the left operand is boolean, throws an exception otherwise.
+Bitwise operators (`&`, `^`, and `|`) do bitwise operations if both the operands are integers, do boolean operations if the left operand is `null` or float, throws an exception otherwise.
 
 ## Xor Expressions
 
@@ -56,13 +56,13 @@ Bitwise operators (`&`, `^`, and `|`) do bitwise operations if both the operands
 
     and_also: or ('&&' or)* ;
 
-Evaluates the left operand, returns it if it is falsy, evaluates the right operand and returns it otherwise.
+Evaluates the left operand, returns it if it is `false` (`null`), evaluates the right operand and returns it otherwise.
 
 ## Or Else Expressions
 
     or_else: and_also ('||' and_also)* ;
 
-Evaluates the left operand, returns it if it is truthy, evaluates the right operand and returns it otherwise.
+Evaluates the left operand, returns it if it is not `false` (`null`), evaluates the right operand and returns it otherwise.
 
 ## Conditional Expressions
 

doc/WalkThrough.md

@@ -12,8 +12,8 @@ This document walks through xemmai language.
     1.5 * 2.0 # => 3.0
     "This is a string."
     null
-    true
-    false
+    true # => 1.0
+    false # => null
 
 ## Variables
 

include/xemmai/ast.h

@@ -81,9 +81,6 @@ struct t_operand
 		size_t v_index;
 	};
 
-	t_operand(bool a_value) : v_tag(e_tag__LITERAL), v_value(reinterpret_cast<t_object*>(a_value ? e_tag__TRUE : e_tag__FALSE))
-	{
-	}
 	t_operand(intptr_t a_value) : v_tag(e_tag__INTEGER), v_integer(a_value)
 	{
 	}
@@ -562,10 +559,6 @@ struct XEMMAI__LOCAL t_emit
 		v_code->v_instructions.push_back(reinterpret_cast<void*>(a_operand));
 		return *this;
 	}
-	t_emit& operator<<(bool a_operand)
-	{
-		return *this << (a_operand ? 1 : 0);
-	}
 	t_emit& operator<<(double a_operand)
 	{
 		union
@@ -624,11 +617,6 @@ struct XEMMAI__LOCAL t_emit
 	}
 };
 
-template<>
-constexpr t_instruction t_emit::f_instruction_of<bool>()
-{
-	return e_instruction__BOOLEAN;
-}
 template<>
 constexpr t_instruction t_emit::f_instruction_of<intptr_t>()
 {

include/xemmai/code.h

@@ -40,12 +40,10 @@ enum t_instruction
 	e_instruction__CLASS,
 	e_instruction__SUPER,
 	e_instruction__NUL,
-	e_instruction__BOOLEAN,
 	e_instruction__INTEGER,
 	e_instruction__FLOAT,
 	e_instruction__INSTANCE,
 	e_instruction__RETURN_NUL,
-	e_instruction__RETURN_BOOLEAN,
 	e_instruction__RETURN_INTEGER,
 	e_instruction__RETURN_FLOAT,
 	e_instruction__RETURN_INSTANCE,

include/xemmai/fiber.h

@@ -265,8 +265,6 @@ inline t_pvalue t_value<T_tag>::f_##a_name() const\
 	auto p = static_cast<t_object*>(*this);\
 	switch (reinterpret_cast<uintptr_t>(p)) {\
 	case e_tag__NULL:\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
 		f_throw(L"not supported."sv);\
 	case e_tag__INTEGER:\
 		return a_operator(v_integer);\
@@ -288,8 +286,6 @@ inline t_pvalue t_value<T_tag>::f_complement() const
 	case e_tag__INTEGER:
 		return ~v_integer;
 	case e_tag__NULL:
-	case e_tag__FALSE:
-	case e_tag__TRUE:
 	case e_tag__FLOAT:
 		f_throw(L"not supported."sv);
 	default:

include/xemmai/float.h

@@ -42,8 +42,6 @@ struct t_type_of<double> : t_derivable<t_bears<double>, t_derived_primitive<doub
 			if (!std::is_same_v<typename t_fundamental<T>::t_type, double>) return reinterpret_cast<uintptr_t>(a_object) >= e_tag__OBJECT && a_object->f_type()->f_derives<typename t_fundamental<T>::t_type>();
 			switch (reinterpret_cast<uintptr_t>(a_object)) {
 			case e_tag__NULL:
-			case e_tag__FALSE:
-			case e_tag__TRUE:
 				return false;
 			case e_tag__INTEGER:
 			case e_tag__FLOAT:

include/xemmai/global.h

@@ -40,7 +40,6 @@ class t_global : public t_library
 	t_slot_of<t_type> v_type_method;
 	t_slot_of<t_type> v_type_throwable;
 	t_slot_of<t_type> v_type_null;
-	t_slot_of<t_type> v_type_boolean;
 	t_slot_of<t_type> v_type_integer;
 	t_slot_of<t_type> v_type_float;
 	t_slot_of<t_type> v_type_string;
@@ -217,7 +216,6 @@ XEMMAI__LIBRARY__TYPE_AS(t_global, t_advanced_lambda<t_lambda_shared>, advanced_
 XEMMAI__LIBRARY__TYPE(t_global, method)
 XEMMAI__LIBRARY__TYPE(t_global, throwable)
 XEMMAI__LIBRARY__TYPE_AS(t_global, std::nullptr_t, null)
-XEMMAI__LIBRARY__TYPE_AS(t_global, bool, boolean)
 XEMMAI__LIBRARY__TYPE_AS(t_global, intptr_t, integer)
 XEMMAI__LIBRARY__TYPE_AS(t_global, double, float)
 XEMMAI__LIBRARY__TYPE(t_global, string)
@@ -245,9 +243,6 @@ XEMMAI__PORTABLE__ALWAYS_INLINE inline t_type* t_value<T_tag>::f_type() const
 	switch (reinterpret_cast<uintptr_t>(p)) {
 	case e_tag__NULL:
 		return f_global()->f_type<std::nullptr_t>();
-	case e_tag__FALSE:
-	case e_tag__TRUE:
-		return f_global()->f_type<bool>();
 	case e_tag__INTEGER:
 		return f_global()->f_type<intptr_t>();
 	case e_tag__FLOAT:
@@ -283,9 +278,6 @@ inline t_pvalue t_value<T_tag>::f_##a_name() const\
 	switch (reinterpret_cast<uintptr_t>(p)) {\
 	case e_tag__NULL:\
 		return t_type_of<std::nullptr_t>::f__##a_name(*this);\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
-		return t_type_of<bool>::f__##a_name(*this);\
 	case e_tag__INTEGER:\
 		return t_type_of<intptr_t>::f__##a_name(v_integer);\
 	case e_tag__FLOAT:\
@@ -317,8 +309,6 @@ inline t_pvalue t_value<T_tag>::f_##a_name(const t_pvalue& a_value) const\
 	auto p = static_cast<t_object*>(*this);\
 	switch (reinterpret_cast<uintptr_t>(p)) {\
 	case e_tag__NULL:\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
 		f_throw(L"not supported."sv);\
 	case e_tag__INTEGER:\
 		return t_type_of<intptr_t>::f__##a_name(v_integer, a_value);\
@@ -339,8 +329,6 @@ inline t_pvalue t_value<T_tag>::f_##a_name(const t_pvalue& a_value) const\
 		f_check<intptr_t>(a_value, L"argument0");\
 		return static_cast<uintptr_t>(v_integer) a_operator f_as<intptr_t>(a_value);\
 	case e_tag__NULL:\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
 	case e_tag__FLOAT:\
 		f_throw(L"not supported."sv);\
 	default:\
@@ -354,9 +342,7 @@ inline t_pvalue t_value<T_tag>::f_##a_name(const t_pvalue& a_value) const\
 	auto p = static_cast<t_object*>(*this);\
 	switch (reinterpret_cast<uintptr_t>(p)) {\
 	case e_tag__NULL:\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
-		return a_operator(p == a_value.v_p);\
+		return a_operator(a_value.f_tag() == e_tag__NULL);\
 	case e_tag__INTEGER:\
 		return t_type_of<intptr_t>::f__##a_name(v_integer, a_value);\
 	case e_tag__FLOAT:\
@@ -365,21 +351,19 @@ inline t_pvalue t_value<T_tag>::f_##a_name(const t_pvalue& a_value) const\
 		XEMMAI__VALUE__BINARY(f_##a_name)\
 	}\
 }
-#define XEMMAI__VALUE__BINARY_BITWISE(a_name, a_operator)\
+#define XEMMAI__VALUE__BINARY_BITWISE(a_name, a_operator, a_null, a_true)\
 template<typename T_tag>\
 inline t_pvalue t_value<T_tag>::f_##a_name(const t_pvalue& a_value) const\
 {\
 	auto p = static_cast<t_object*>(*this);\
 	switch (reinterpret_cast<uintptr_t>(p)) {\
-	case e_tag__FALSE:\
-	case e_tag__TRUE:\
-		return static_cast<bool>(f_as<bool>(*this) a_operator f_as<bool>(a_value));\
+	case e_tag__NULL:\
+		return a_null;\
 	case e_tag__INTEGER:\
 		f_check<intptr_t>(a_value, L"argument0");\
 		return v_integer a_operator f_as<intptr_t>(a_value);\
-	case e_tag__NULL:\
 	case e_tag__FLOAT:\
-		f_throw(L"not supported."sv);\
+		return a_true;\
 	default:\
 		XEMMAI__VALUE__BINARY(f_##a_name)\
 	}\
@@ -398,9 +382,9 @@ XEMMAI__VALUE__BINARY_ARITHMETIC(greater, >)
 XEMMAI__VALUE__BINARY_ARITHMETIC(greater_equal, >=)
 XEMMAI__VALUE__BINARY_EQUALITY(equals, )
 XEMMAI__VALUE__BINARY_EQUALITY(not_equals, !)
-XEMMAI__VALUE__BINARY_BITWISE(and, &)
-XEMMAI__VALUE__BINARY_BITWISE(xor, ^)
-XEMMAI__VALUE__BINARY_BITWISE(or, |)
+XEMMAI__VALUE__BINARY_BITWISE(and, &, false, a_value)
+XEMMAI__VALUE__BINARY_BITWISE(xor, ^, a_value, a_value ? false : *this)
+XEMMAI__VALUE__BINARY_BITWISE(or, |, a_value, *this)
 
 template<typename T>
 inline t_object* t_type::f_new(auto&&... a_xs)

include/xemmai/integer.h

@@ -38,8 +38,6 @@ struct t_type_of<intptr_t> : t_derivable<t_bears<intptr_t>, t_derived_primitive<
 			case e_tag__INTEGER:
 				return true;
 			case e_tag__NULL:
-			case e_tag__FALSE:
-			case e_tag__TRUE:
 			case e_tag__FLOAT:
 				return false;
 			default:

include/xemmai/map.h

@@ -2,7 +2,6 @@
 #define XEMMAI__MAP_H
 
 #include "sharable.h"
-#include "boolean.h"
 #include "integer.h"
 
 namespace xemmai
@@ -87,7 +86,7 @@ class t_map : public t_sharable
 		}
 		static bool f_equals(const t_entry& a_p, size_t a_hash, const t_pvalue& a_key)
 		{
-			return a_p.v_hash == a_hash && f_as<bool>(a_p.v_key.f_equals(a_key));
+			return a_p.v_hash == a_hash && a_p.v_key.f_equals(a_key);
 		}
 		XEMMAI__PORTABLE__ALWAYS_INLINE t_entry* f_find(const t_pvalue& a_key) const
 		{

include/xemmai/object.h

@@ -327,7 +327,7 @@ inline void t_slot_of<T>::f_construct(t_object* a_value)
 	v_slot = a_value;
 }
 
-template<typename T>
+template<typename T, typename>
 struct t_type::t_cast
 {
 	static T f_as(auto&& a_object)
@@ -356,8 +356,6 @@ struct t_type::t_cast<T*>
 		switch (reinterpret_cast<uintptr_t>(a_object)) {
 		case e_tag__NULL:
 			return true;
-		case e_tag__FALSE:
-		case e_tag__TRUE:
 		case e_tag__INTEGER:
 		case e_tag__FLOAT:
 			return false;

include/xemmai/type.h

@@ -34,6 +34,12 @@ struct t_fundamental<t_value<T_tag>>
 	using t_type = t_object;
 };
 
+template<>
+struct t_fundamental<bool>
+{
+	using t_type = t_object;
+};
+
 template<typename T, size_t... A_Is>
 static constexpr std::array<T, sizeof...(A_Is) + 1> f_append(const std::array<T, sizeof...(A_Is)>& a_xs, std::index_sequence<A_Is...>, T a_x)
 {
@@ -92,7 +98,7 @@ struct t_fields
 template<>
 struct t_type_of<t_object>
 {
-	template<typename> struct t_cast;
+	template<typename, typename = void> struct t_cast;
 	template<typename T_tag>
 	struct t_cast<const t_value<T_tag>&>
 	{
@@ -105,6 +111,18 @@ struct t_type_of<t_object>
 			return true;
 		}
 	};
+	template<typename T>
+	struct t_cast<T, std::enable_if_t<std::is_same_v<std::remove_const_t<std::remove_reference_t<T>>, bool>>>
+	{
+		static bool f_as(auto&& a_object)
+		{
+			return a_object;
+		}
+		static bool f_is(auto&&)
+		{
+			return true;
+		}
+	};
 	using t_library = t_global;
 
 	static XEMMAI__TYPE__IDS_MODIFIER std::array<t_type_id, 1> V_ids{f_type_id<t_object>()};