Modifies the parser to parse one statement on each parser call.

This makes the IF/THEN accept only one statement at the end, but allows
the parser to generate bigger code for the long lines.

Author: dmsc

src/basic.syn

@@ -354,7 +354,7 @@ PRINT_NEXT:
 
 # Parse multi-line IF
 THEN_OR_MULTILINE:
-        "Then" PARSE_START E_POP_IF
+        "Then" PARSE_STATEMENT E_POP_IF
         pass
 
 VAR_CREATE_TYPE:
@@ -517,7 +517,6 @@ DATA_VAR:
 # Parse a line
 PARSE_LINE_COMMAND:
 	"." E_REM
-	"'" E_REM
 	"?" IO_CHAN_OPT PRINT_EXPR
 	"PRint" IO_CHAN_OPT PRINT_EXPR
         "INput" INPUT_STR INPUT_VAR_LIST emit TOK_IOCHN0
@@ -577,17 +576,18 @@ PARSE_LINE_ASSIGN: &LOW_ERROR
         VAR_FP_LVALUE EQUAL FP_EXPR emit TOK_FP_STORE
 #@endif FASTBASIC_FP
 
-PARSE_LINE: statement or variable assignment
+SKIP_COMMENT:
+	"'" E_REM
+        E_EOL
+        pass
+
+PARSE_STATEMENT: statement or variable assignment
         PARSE_LINE_COMMAND E_EOL
         PARSE_LINE_ASSIGN
-
-PARSE_MORE: comment, end of line or new line
-        ":" PARSE_LINE PARSE_MORE
-        "'" E_REM
-        E_EOL
+        pass
 
 PARSE_START:
-        PARSE_LINE PARSE_MORE
-        PARSE_MORE
+        ":" PARSE_START
+        PARSE_STATEMENT SKIP_COMMENT
 
 # vi:syntax=perl

src/compiler/main.cc

@@ -175,22 +175,26 @@ int main(int argc, char **argv)
         if( do_debug )
             std::cerr << iname << ": parsing line " << ln << "\n";
         s.new_line(line, ln);
-        if( !SMB_PARSE_START(s) || s.pos != line.length() )
+        while( s.pos != line.length() )
         {
-            std::cerr << iname << ":" << ln << ":" << s.max_pos << ": parse error";
-            if( !s.saved_error.empty() )
-                std::cerr << ", expected " << s.saved_error;
-            std::cerr << "\n";
-            size_t min = 0, max = s.str.length();
-            if( s.max_pos > 40 ) min = s.max_pos - 40;
-            if( s.max_pos + 40 < max ) max = s.max_pos + 40;
-            for(auto i = min; i<s.max_pos; i++)
-                std::cerr << s.str[i];
-            std::cerr << "<--- HERE -->";
-            for(auto i = s.max_pos; i<max; i++)
-                std::cerr << s.str[i];
-            std::cerr << "\n";
-            return 1;
+            if( !SMB_PARSE_START(s) || ( s.pos != line.length() && !s.peek(':') )  )
+            {
+                std::cerr << iname << ":" << ln << ":" << s.max_pos << ": parse error";
+                std::cerr << "pos=" << s.pos << ", len=" << line.length() << "\n";
+                if( !s.saved_error.empty() )
+                    std::cerr << ", expected " << s.saved_error;
+                std::cerr << "\n";
+                size_t min = 0, max = s.str.length();
+                if( s.max_pos > 40 ) min = s.max_pos - 40;
+                if( s.max_pos + 40 < max ) max = s.max_pos + 40;
+                for(auto i = min; i<s.max_pos; i++)
+                    std::cerr << s.str[i];
+                std::cerr << "<--- HERE -->";
+                for(auto i = s.max_pos; i<max; i++)
+                    std::cerr << s.str[i];
+                std::cerr << "\n";
+                return 1;
+            }
         }
     }
     if( do_debug )

src/parse.asm

@@ -306,12 +306,6 @@ pcall:
         pha
         bcs     parser_sub
 
-call_ax1:
-        pha
-        txa
-        pha
-        rts
-
 pemit_ret:
         jsr     emit_sub
 
@@ -330,6 +324,8 @@ pexit_ok:
         ; Check if we are at end of line
         ldy     bpos
         lda     (bptr), y
+        cmp     #':'            ; Colon: continue parsing line
+        beq     parse_start
         cmp     #$9B
         bne     set_parse_error
 line_ok:
@@ -354,6 +350,12 @@ skip_chars:
         tax
         bcc     ploop_nofetch
 
+call_ax1:
+        pha
+        txa
+        pha
+        rts
+
 pexit_err:
         pla
         sta     opos