Implement +PLACE

lib/core.fs

@@ -628,6 +628,12 @@ include ../shared/core.fs
 : place ( c-addr1 u1 c-addr2 -- )
   over >r rot over char+ r> move c! ;
 
+: +place ( c-addr1 u1 c-addr2 -- )
+  over over >r >r
+  count chars +
+  swap chars move
+  r> r@ c@ + r> c! ;
+
 : bounds ( addr u – addr+u addr )
   over + swap ;
 

test/core/test-plus-place.fs

@@ -0,0 +1,7 @@
+create note 256 chars allot
+
+: main
+  s" Forth " note  place
+  s" for "   note +place
+  s" GB"     note +place
+  note ;

test/core/test-plus-place.js

@@ -0,0 +1,13 @@
+const gb = require("../gbtest")(__filename);
+
+const readCountedString = (addr) => {
+  const len = gb.memory[addr]
+  const chars = gb.memory.slice(addr + 1, addr + 1 + len)
+  return String.fromCharCode(...chars)
+}
+
+test("plus-place", () => {
+  gb.run();
+  expect(gb.stack.length).toBe(1);
+  expect(readCountedString(gb.stack[0])).toBe("Forth for GB")
+});