[main.c] Refactor handling of flags...

- Add subcommand `dump_tokens`.
- Remove -d flag.

diff --git a/grammar.txt b/grammar.txt
deleted file mode 100644 (file)
index 056d114..0000000
--- a/grammar.txt
+++ /dev/null
@@ -1,35 +0,0 @@
-expression -> literal | unary | binary | grouping ;
-grouping   -> "(" expression ")" ;
-literal    -> NUMBER | STRING | "true" | "false" | "nil" ;
-unary      -> ( "!" | "-" ) expression ;
-binary     -> expression operator expression ;
-operator   -> "==" | "!=" | "<" | "<=" | ">" | ">=" |
-              "+" | "-" | "*" | "/" ;
-
-
-NUMBER     -> "[0-9]" "."? "[0-9]" ;
-STRING     -> \" "[a-zA-Z]"* \" ;
-
-
-So expression could be:
-1. 
-       unary =>
-       !expression =>
-       !literal =>
-       !NUMBER =>
-       !4
-
-2.
-       grouping =>
-       (expression) =>
-       (binary) =>
-       (expression operator expression) =>
-       (literal operator expression) =>
-       (NUMBER operator expression) => 
-       (5.8 operator expression) =>
-       (5.8 * expression) =>
-       (5.8 * unary) =>
-       (5.8 * -expression) =>
-       (5.8 * -literal) =>
-       (5.8 * -NUMBER) =>
-       (5.8 * -8)

diff --git a/main.c b/main.c
index 0cb5b8d644958152ecc0a3e8f9778091d79817d4..9acb7a655fd8e8374c7cce7bb98dd77fd1b560c1 100644 (file)
--- a/main.c
+++ b/main.c
@@ -241,7 +241,7 @@ void print_expression(FILE *f, Expression e);
 ///
 
 void usage(const char *program) {
-    info("Usage: %s [flag(s)] <file>", program);
+    info("Usage: %s [subcommand] [flag(s)] <file>", program);
 }
 
 void help(const char *program) {
@@ -249,9 +249,11 @@ void help(const char *program) {
 
     info("");
     info("Flags: ");
-    info("  -h      Prints this help message.");
-    info("  -v      Prints the version of the compiler.");
-    info("  -d      Enables debug printing.");
+    info("  -h           Prints this help message.");
+    info("  -v           Prints the version of the compiler.");
+    info("Subcommands: ");
+    info("  help         Prints this help message.");
+    info("  dump_tokens  Dumps the tokens scanned and exit.");
 }
 
 void print_loc(FILE *f, Location loc) {
@@ -1326,47 +1328,50 @@ typedef struct {
 int main(int argc, char **argv) {
     const char *program = shift_args(argv, argc);
 
-    Flags flags = {0};
-
     const char *filename = NULL;
-    while (argc > 0) {
-        const char *arg = shift_args(argv, argc);
 
-        if (*arg == '-' || *arg == '/') {
-            const char *flag = arg; // Including the prefix
+    bool dump_tokens = false;
 
-            da_append(flags, flag);
-        } else {
-            filename = arg;
-        }
-    }
-
-    // Parse flags
-    for (size_t i = 0; i < flags.count; ++i) {
-        const char *flag = flags.items[i];
-
-        char prefix = *flag;
+    while (argc > 0) {
+        const char *arg = shift_args(argv, argc);
 
-        flag += 1; // Remove prefix
+        if (*arg == '-') {
+            const char *flag = arg+1;
+            // TODO: We only support single char flags for now, eg: -h, -V
+            if (*flag == '-') {
+                log_error("We only support single char flags for now!");
+                return 1;
+            } else if (*flag == 'h') {
+                help(program);
+                return 0;
+            } else if (*flag == 'v') {
+                log_info("Compiler Version: %s", COMPILER_VERSION);
+                return 0;
+            } else {
+                log_error("Invalid flag `%s`", flag);
+                return 1;
+            }
 
-        if (strcmp(flag, "h") == 0) {
-            help(program);
-            exit(0);
-        } else if (strcmp(flag, "v") == 0) {
-            info("Compiler Version: "COMPILER_VERSION);
-            exit(0);
-        } else if (strcmp(flag, "d") == 0) {
-            DEBUG_PRINT = true;
         } else {
-            error("Invalid flag '%c%s'...", prefix, flag);
-            exit(1);
+            if (strcmp(arg, "help") == 0) {
+                help(program);
+                return 0;
+            } else if (strcmp(arg, "dump_tokens") == 0) {
+                dump_tokens = true;
+            } else {
+                if (filename == NULL) {
+                    filename = arg;
+                } else {
+                    log_error("Invalid subcommand `%s`", arg);
+                    return 1;
+                }
+            }
         }
     }
 
     if (filename == NULL) {
         error("Please provide a filename!");
         usage(program);
-        da_free(flags);
         return 1;
     }
 
@@ -1374,6 +1379,14 @@ int main(int argc, char **argv) {
 
     Tokens tokens = lex(&l);
 
+    if (dump_tokens) {
+        for (size_t i = 0; i < tokens.count; ++i) {
+            print_token(stdout, tokens.items[i]);
+            printf("\n");
+        }
+        return 0;
+    }
+
     Parser p = make_parser(tokens);
 
     Arena expr_arena = arena_make(0);
@@ -1385,6 +1398,5 @@ int main(int argc, char **argv) {
     arena_free(&expr_arena);
     free_parser(&p);
     free_lexer(&l);
-    da_free(flags);
     return 0;
 }