✨ float arithmetic.

doc/grammar.bnf

@@ -16,3 +16,4 @@ LITERAL ::=
 BUILTIN ::=
 | int
 | bool
+| float

features/float.sk

@@ -0,0 +1,10 @@
+assert 6.200 eq 6.2
+assert 5.2 + 1.2 eq 6.4
+assert 5.2 - 1.2 eq 4.0
+assert 5.2 * 1.2 eq 6.24
+assert 5.2 / 2.0 eq 2.6
+assert 12.0 % 2.5 eq 2.0
+assert 25.0 ^ 0.5 eq 5.0
+
+assert 1 + 1.0 eq 2.0
+assert 3.0 * 2 eq 6.0

lib/include/lexer.h

@@ -30,6 +30,7 @@ bool lexer_next_is(struct lexer* self, TokenKind kind);
 void lexer_consume_next(struct lexer* self);
 struct token* lexer_try_new_next(struct lexer* self);
 struct token* lexer_try_scan_int(struct lexer* self);
+struct token* lexer_try_scan_float(struct lexer* self);
 struct token* lexer_try_scan_text(struct lexer* self,
                                   char const* text,
                                   TokenKind kind);

lib/include/node.h

@@ -10,7 +10,7 @@ G(NODE_ADD), G(NODE_SUB), G(NODE_MUL),\
 G(NODE_DIV), G(NODE_POW), G(NODE_MOD),\
 G(NODE_USUB), G(NODE_ASSERT_EQ), \
 G(NODE_BOOL), G(NODE_AND), G(NODE_OR), \
-G(NODE_NOT)
+G(NODE_NOT), G(NODE_FLOAT)
 
 SK_ENUM_H(NodeKind, NODE_KIND);
 

lib/include/state.h

@@ -51,6 +51,11 @@ SK state_push(struct state* self,
 
 SK state_push_int(struct state* self, int integer, int line);
 SK state_push_bool(struct state* self, bool boolean, int line);
+SK state_push_float(struct state* self, double real, int line);
+
+TypeKind state_common_num_type(struct state* self, SK lhs, SK rhs);
+double state_as_real(struct state* self, SK lhs);
+int state_line(struct state* self, SK lhs);
 
 SK state_add(struct state* self);
 SK state_sub(struct state* self);

lib/include/token.h

@@ -11,7 +11,7 @@ G(TOKEN_MUL), G(TOKEN_DIV), G(TOKEN_MOD), \
 G(TOKEN_POW), G(TOKEN_OPAR), G(TOKEN_CPAR), \
 G(TOKEN_ASSERT), G(TOKEN_ASSERT_EQ), \
 G(TOKEN_BOOL), G(TOKEN_AND), G(TOKEN_OR), \
-G(TOKEN_NOT)
+G(TOKEN_NOT), G(TOKEN_FLOAT)
 
 SK_ENUM_H(TokenKind, TOKEN_KIND);
 

lib/include/value.h

@@ -5,13 +5,14 @@
 #include "node.h"
 
 #define TYPE_KIND(G) \
-G(TYPE_INT), G(TYPE_BOOL)
+G(TYPE_INT), G(TYPE_BOOL), G(TYPE_FLOAT)
 
 SK_ENUM_H(TypeKind, TYPE_KIND);
 
 union val
 {
     int integer;
+    double real;
     bool boolean;
 };
 

lib/src/compiler.c

@@ -62,6 +62,13 @@ void compiler_compile(struct compiler* self,
                                    val);
         } break;
 
+        case NODE_FLOAT: {
+            union val val;
+            val.real = atof(node->token->value);
+            compiler_compile_value(self, node, prog, TYPE_FLOAT,
+                                   val);
+        } break;
+
         case NODE_ADD: {
             compiler_compile_children(self, node, prog);
             prog_add_instr(prog, OP_ADD, SK_NO_PARAM);

lib/src/exec.c

@@ -74,6 +74,14 @@ void exec_execute(struct exec* self,
                         );
                     } break;
 
+                    case TYPE_FLOAT: {
+                        state_push_float(
+                            state,
+                            constant->val.real,
+                            constant->line
+                        );
+                    } break;
+
                     case TYPE_BOOL: {
                         state_push_bool(
                             state,

lib/src/lexer.c

@@ -133,6 +133,11 @@ struct token* lexer_try_new_next(struct lexer* self)
 
     struct token* tok = NULL;
 
+    if ( (tok=lexer_try_scan_float(self)) )
+    {
+        return tok;
+    }
+
     if ( (tok=lexer_try_scan_int(self)) )
     {
         return tok;
@@ -212,6 +217,60 @@ struct token* lexer_try_scan_int(struct lexer* self)
     return tok;
 }
 
+struct token* lexer_try_scan_float(struct lexer* self)
+{
+    assert(self);
+    size_t cursor = self->context.cursor;
+    struct str value;
+    str_init(&value);
+
+    if (cursor < self->len
+        && self->source[cursor] == '-')
+    {
+        str_push(&value, self->source[cursor]);
+        cursor++;
+    }
+
+    while (cursor < self->len
+           && isdigit(self->source[cursor]))
+    {
+        str_push(&value, self->source[cursor]);
+        cursor++;
+    }
+
+    if (cursor >= self->len
+        || self->source[cursor] != '.')
+    {
+        str_free(&value);
+        return NULL;
+    }
+
+    str_push(&value, self->source[cursor]);
+    cursor++;
+
+    while (cursor < self->len
+           && isdigit(self->source[cursor]))
+    {
+        str_push(&value, self->source[cursor]);
+        cursor++;
+    }
+    
+    struct token* tok = NULL;
+
+    if (value.size > 0
+    && (value.value[0] != '-' || value.size > 1))
+    {
+        tok = malloc(sizeof(struct token));
+        token_init(tok, TOKEN_FLOAT,
+                   value.value, self->context.line);
+
+        self->context.cursor = cursor;
+    }
+
+    str_free(&value);
+    return tok;
+}
+
 struct token* lexer_try_scan_text(struct lexer* self,
                                   char const* text,
                                   TokenKind kind)

lib/src/parser.c

@@ -50,18 +50,40 @@ struct node* parser_try_root(struct parser* self)
 
     node_init(node, NODE_ROOT, tok);
 
+    struct str error_str;
+    str_init(&error_str);
+
     while (!lexer_is_at_end(&self->lexer))
     {
         struct node* expr = SK_TRY(parser_try_expr);
 
+        if (!expr)
+        {
+            while (self->lexer.context.cursor < self->lexer.len
+            && !lexer_is_sep(&self->lexer,
+                             self->lexer.context.cursor))
+            {
+                str_push(&error_str,
+                         self->lexer.source[
+                         self->lexer.context.cursor
+                         ]);
+                self->lexer.context.cursor++;
+            }
+
+            break;
+        }
+
         node_push_new_child(node, expr);
     }
 
     if (self->lexer.context.cursor < self->lexer.len)
     {
-        errors_push(self->lexer.context.line, "unexpected end");
+        errors_push(self->lexer.context.line,
+                    "unexpected end near '%s'",
+                    error_str.value);
     }
 
+    str_free(&error_str);
     return node;
 }
 
@@ -87,12 +109,19 @@ struct node* parser_try_assert(struct parser* self)
     struct token* tok = lexer_try_new_next(&self->lexer);
 
     struct node* lhs = SK_TRY(parser_try_expr);
-    if (!lhs) { return NULL; }
+    if (!lhs)
+    {
+        token_free(tok); free(tok);
+        return NULL;
+    }
 
     if (!lexer_next_is(&self->lexer, TOKEN_ASSERT_EQ))
     {
         token_free(tok);
         free(tok);
+
+        node_free(lhs);
+        free(lhs);
         return NULL;
     }
 
@@ -102,6 +131,8 @@ struct node* parser_try_assert(struct parser* self)
     {
         token_free(tok);
         free(tok);
+        node_free(lhs);
+        free(lhs);
         return NULL;
     }
 
@@ -398,5 +429,16 @@ struct node* parser_try_builtin(struct parser* self)
         return node;
     }
 
+    if (lexer_next_is(&self->lexer, TOKEN_FLOAT))
+    {
+        struct node* node = malloc(sizeof(struct node));
+
+        node_init(node,
+                  NODE_FLOAT,
+                  lexer_try_new_next(&self->lexer));
+
+        return node;
+    }
+
     return NULL;
 }

lib/src/state.c

@@ -146,19 +146,86 @@ SK state_push_bool(struct state* self, bool boolean, int line)
     return state_push(self, TYPE_BOOL, val, line);
 }
 
+SK state_push_float(struct state* self, double real, int line)
+{
+    assert(self);
+    union val val;
+    val.real = real;
+    return state_push(self, TYPE_FLOAT, val ,line);
+}
+
+TypeKind state_common_num_type(struct state* self, SK lhs, SK rhs)
+{
+    assert(self);
+
+    struct value const* left = state_try_get_value(self, lhs);
+    struct value const* right = state_try_get_value(self, rhs);
+
+    if (left->type == TYPE_FLOAT
+        || right->type == TYPE_FLOAT)
+    {
+        return TYPE_FLOAT;
+    }
+
+    return TYPE_INT;
+}
+
+double state_as_real(struct state* self, SK lhs)
+{
+    assert(self);
+
+    struct value* value = state_try_get_value(self, lhs);
+
+    if (value->type == TYPE_INT)
+    {
+        return value->val.integer;
+    }
+    else if (value->type == TYPE_FLOAT)
+    {
+        return value->val.real;
+    }
+
+    errors_push(value->line, "expected a number, got '%s'",
+                TypeKindStr[value->type] + strlen("TYPE_"));
+    return 0.0;
+}
+
+int state_line(struct state* self, SK lhs)
+{
+    assert(self);
+    struct value const* value = state_try_get_value(self, lhs);
+    return value->line;
+}
+
 SK state_add(struct state* self)
 {
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        left->val.integer + right->val.integer,
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            state_as_real(self, lhs) + state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            state_as_real(self, lhs) + state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot addition");
+        return 0;
+    }
 }
 
 SK state_sub(struct state* self)
@@ -166,27 +233,60 @@ SK state_sub(struct state* self)
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        left->val.integer - right->val.integer,
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            state_as_real(self, lhs) - state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            state_as_real(self, lhs) - state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot substract");
+        return 0;
+    }
 }
 
 SK state_usub(struct state* self)
 {
     SK lhs = state_pop(self);
+    struct value const* value = state_try_get_value(self, lhs);
+    TypeKind type = value->type;
 
-    struct value* left = state_try_get_value(self, lhs);
-
-    return state_push_int(
-        self,
-        -left->val.integer,
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            -state_as_real(self, lhs),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            -state_as_real(self, lhs),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot apply unary substraction");
+        return 0;
+    }
 }
 
 SK state_mul(struct state* self)
@@ -194,14 +294,30 @@ SK state_mul(struct state* self)
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        left->val.integer * right->val.integer,
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            state_as_real(self, lhs) * state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            state_as_real(self, lhs) * state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot multiply");
+        return 0;
+    }
 }
 
 SK state_div(struct state* self)
@@ -209,14 +325,30 @@ SK state_div(struct state* self)
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        left->val.integer / right->val.integer,
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            state_as_real(self, lhs) / state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            state_as_real(self, lhs) / state_as_real(self, rhs),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot divide");
+        return 0;
+    }
 }
 
 SK state_mod(struct state* self)
@@ -224,14 +356,32 @@ SK state_mod(struct state* self)
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        fmod(left->val.integer, right->val.integer),
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            fmod(state_as_real(self, lhs),
+                 state_as_real(self, rhs)),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            fmod(state_as_real(self, lhs),
+                 state_as_real(self, rhs)),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot apply mod");
+        return 0;
+    }
 }
 
 SK state_pow(struct state* self)
@@ -239,14 +389,32 @@ SK state_pow(struct state* self)
     SK rhs = state_pop(self);
     SK lhs = state_pop(self);
 
-    struct value* left = state_try_get_value(self, lhs);
-    struct value* right = state_try_get_value(self, rhs);
+    TypeKind type = state_common_num_type(self, lhs, rhs);
 
-    return state_push_int(
-        self,
-        powf(left->val.integer, right->val.integer),
-        left->line
-    );
+    if (type == TYPE_INT)
+    {
+        return state_push_int(
+            self,
+            powf(state_as_real(self, lhs),
+                 state_as_real(self, rhs)),
+            state_line(self, lhs)
+        );
+    }
+    else if (type == TYPE_FLOAT)
+    {
+        return state_push_float(
+            self,
+            powf(state_as_real(self, lhs),
+                 state_as_real(self, rhs)),
+            state_line(self, lhs)
+        );
+    }
+    else
+    {
+        errors_push(state_line(self, lhs),
+                    "cannot apply pow");
+        return 0;
+    }
 }
 
 SK state_and(struct state* self)

lib/src/value.c

@@ -47,6 +47,10 @@ void value_str(struct value* self, struct str* dest)
             str_format(dest, "%d", self->val.integer);
         } break;
 
+        case TYPE_FLOAT: {
+            str_format(dest, "%f", self->val.real);
+        } break;
+
         case TYPE_BOOL: {
             str_format(dest, "%s",
                        self->val.boolean ? "true" : "false");

tests/lexer.h

@@ -70,12 +70,24 @@ static void test_lexer_bool()
                "NOT"
     );
 }
+
+static void test_lexer_float()
+{
+    test_lexer(".4 7. 2.3 -6.12", 4,
+               "FLOAT[.4]",
+               "FLOAT[7.]",
+               "FLOAT[2.3]",
+               "FLOAT[-6.12]"
+    );
+}
+
 void register_lexer()
 {
     CU_pSuite suite = CU_add_suite("Lexer", 0, 0);
     CU_add_test(suite, "Integers", test_lexer_int);
     CU_add_test(suite, "Assertions", test_lexer_assert);
     CU_add_test(suite, "Booleans", test_lexer_bool);
+    CU_add_test(suite, "Floats", test_lexer_float);
 }
 
 #endif