Add type signature to def statements

Currently mandatory, may be optional once we have type inference.

5 files changed, 121 insertions, 103 deletions

diff --git a/src/main.c b/src/main.c
index 7a24895..c545f6a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -7,6 +7,7 @@
 #include "string_view.c"
 #include "errors.c"
 #include "lexer.c"
+#include "nodes.c"
 #include "parser.c"
 // #include "ir.h"
 // #include "compiler.h"
diff --git a/src/nodes.c b/src/nodes.c
new file mode 100644
index 0000000..63e9b1f
--- /dev/null
+++ b/src/nodes.c
@@ -0,0 +1,61 @@
+#include "nodes.h"
+
+Node *
+alloc_node(NodeType type) {
+    // TODO: Use a bump allocator?
+    // TODO: Free memory!
+    Node *node = malloc(sizeof(Node));
+    node->type = type;
+    return node;
+}
+
+void
+print_node(Node *node) {
+    switch (node->type) {
+        case NODE_NUMBER: {
+            if (node->number.negative) {
+                printf("-");
+            }
+            if (node->number.fractional != 0) {
+                printf("%zu.%zu", node->number.integral, node->number.fractional);
+            } else {
+                printf("%zu", node->number.integral);
+            }
+        } break;
+        case NODE_SYMBOL:
+        case NODE_STRING: {
+            sv_write(&node->string);
+        } break;
+        case NODE_BOOL: {
+            if (node->boolean) {
+                printf("true");
+            } else {
+                printf("false");
+            }
+        } break;
+        case NODE_BUILTIN: {
+            printf("({%s}", token_str[node->builtin.type]);
+            size_t n_args = array_size(node->builtin.args);
+            if (n_args != 0) {
+                printf(" ");
+            }
+            for (size_t i = 0; i < n_args; ++i) {
+                print_node(node->builtin.args[i]);
+                if (i < n_args - 1) {
+                    printf(" ");
+                }
+            }
+            printf(")");
+        } break;
+        case NODE_DEF: {
+            printf("(def ");
+            print_node(node->def.symbol);
+            printf(":");
+            sv_write(&node->def.type);
+            printf(" ");
+            print_node(node->def.value);
+            printf(")");
+        } break;
+        default: { printf("{#unknown#}"); } break;
+    }
+}
diff --git a/src/nodes.h b/src/nodes.h
new file mode 100644
index 0000000..e6ceb50
--- /dev/null
+++ b/src/nodes.h
@@ -0,0 +1,45 @@
+#ifndef BDL_NODES_H
+#define BDL_NODES_H
+
+typedef enum NodeType {
+    NODE_BUILTIN,
+    NODE_NUMBER,
+    NODE_BOOL,
+    NODE_STRING,
+    NODE_SYMBOL,
+    NODE_DEF,
+} NodeType;
+
+typedef struct Node {
+    NodeType type;
+
+    union {
+        // Numbers.
+        struct {
+            bool negative;
+            size_t integral;
+            size_t fractional;
+        } number;
+
+        // String/symbol.
+        StringView string;
+
+        // Boolean.
+        bool boolean;
+
+        // Builtin primitive.
+        struct {
+            TokenType type;
+            struct Node **args;
+        } builtin;
+
+        // Variable definition.
+        struct {
+            struct Node *symbol;
+            struct Node *value;
+            StringView type;
+        } def;
+    };
+} Node;
+
+#endif // BDL_NODES_H
diff --git a/src/parser.c b/src/parser.c
index 434ae98..cc94fd2 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -1,15 +1,6 @@
 #include "parser.h"
 #include "darray.h"
 
-Node *
-alloc_node(NodeType type) {
-    // TODO: Use a bump allocator?
-    // TODO: Free memory!
-    Node *node = malloc(sizeof(Node));
-    node->type = type;
-    return node;
-}
-
 Token
 next_token(Parser *parser) {
     return parser->tokens[parser->current++];
@@ -154,7 +145,18 @@ parse_def(Parser *parser) {
         return NULL;
     }
 
-    // TODO: Check if it has type annotation.
+    // TODO: Making type checking mandatory for now until we introduce
+    // type inference.
+    Token next = next_token(parser);
+    if (next.type != TOKEN_COLON) {
+        push_error(ERR_TYPE_PARSER, ERR_MALFORMED_EXPR, op.line, op.col);
+        return NULL;
+    }
+    Token type_name = next_token(parser);
+    if (type_name.type != TOKEN_SYMBOL) {
+        push_error(ERR_TYPE_PARSER, ERR_MALFORMED_EXPR, op.line, op.col);
+        return NULL;
+    }
 
     Node *value = parse_next(parser);
     if (value == NULL) {
@@ -171,9 +173,7 @@ parse_def(Parser *parser) {
     Node *node = alloc_node(NODE_DEF);
     node->def.symbol = symbol;
     node->def.value = value;
-
-    // TODO: Register variable in symbol table.
-
+    node->def.type = type_name.value;
     return node;
 }
 
@@ -221,55 +221,6 @@ parse_next(Parser *parser) {
 }
 
 void
-print_node(Node *node) {
-    switch (node->type) {
-        case NODE_NUMBER: {
-            if (node->number.negative) {
-                printf("-");
-            }
-            if (node->number.fractional != 0) {
-                printf("%zu.%zu", node->number.integral, node->number.fractional);
-            } else {
-                printf("%zu", node->number.integral);
-            }
-        } break;
-        case NODE_SYMBOL:
-        case NODE_STRING: {
-            sv_write(&node->string);
-        } break;
-        case NODE_BOOL: {
-            if (node->boolean) {
-                printf("true");
-            } else {
-                printf("false");
-            }
-        } break;
-        case NODE_BUILTIN: {
-            printf("({%s}", token_str[node->builtin.type]);
-            size_t n_args = array_size(node->builtin.args);
-            if (n_args != 0) {
-                printf(" ");
-            }
-            for (size_t i = 0; i < n_args; ++i) {
-                print_node(node->builtin.args[i]);
-                if (i < n_args - 1) {
-                    printf(" ");
-                }
-            }
-            printf(")");
-        } break;
-        case NODE_DEF: {
-            printf("(def ");
-            print_node(node->def.symbol);
-            printf(" ");
-            print_node(node->def.value);
-            printf(")");
-        } break;
-        default: { printf("{#unknown#}"); } break;
-    }
-}
-
-void
 parse(Token *tokens) {
     Parser parser = {
         .tokens = tokens,
diff --git a/src/parser.h b/src/parser.h
index 6a4401e..47316b9 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -2,53 +2,13 @@
 #define BDL_PARSER_H
 
 #include "lexer.h"
+#include "nodes.h"
 
 typedef struct Parser {
     Token *tokens;
     size_t current;
 } Parser;
 
-typedef enum NodeType {
-    NODE_BUILTIN,
-    NODE_NUMBER,
-    NODE_BOOL,
-    NODE_STRING,
-    NODE_SYMBOL,
-    NODE_DEF,
-} NodeType;
-
-typedef struct Node {
-    NodeType type;
-
-    union {
-        // Numbers.
-        struct {
-            bool negative;
-            size_t integral;
-            size_t fractional;
-        } number;
-
-        // String/symbol.
-        StringView string;
-
-        // Boolean.
-        bool boolean;
-
-        // Builtin primitive.
-        struct {
-            TokenType type;
-            struct Node **args;
-        } builtin;
-
-        // Variable definition.
-        struct {
-            struct Node *symbol;
-            struct Node *value;
-            // TODO: type information
-        } def;
-    };
-} Node;
-
 void parse(Token *tokens);
 Node * parse_next(Parser *parser);