Merge pull request #4 from nineties/add_private

Add private

bootstrap.fs

@@ -2511,6 +2511,38 @@ need-defined (read)
         @ &latest !
 ;
 
+( === Private and Export === )
+
+\ Words defined between private{ ... }private
+\ are invisible outside of this scope.
+\ You can export words using 'export'.
+\ : name .... ; export
+
+: private{
+    align
+    latest ,
+    here cell- &latest !
+    s"  private-marker" dup strlen
+    c, strcpy, align
+;
+
+: }private
+    s"  private-marker" find! name>link &latest !
+;
+
+: export
+    \ Move latest to the boottm of the dictionary.
+    latest
+    begin dup name>link while
+        name>link
+    repeat
+    latest
+    ( last latest )
+    dup name>link &latest !
+    0 over !
+    swap !
+;
+
 ( === Primitive Instructions === )
 
 : insn:docol docol ;
@@ -2553,7 +2585,7 @@ need-defined (read)
         include included source >in
         next-arg shift-args arg argv argc version runtime copyright
 
-        [if] [unless] [else] [then] defined?
+        [if] [unless] [else] [then] defined? private{ }private export
         open-file close-file write-file flush-file
         read-file key-file read-line
         R/W W/O R/O EOF

runtests.fs

@@ -13,5 +13,7 @@ include test/utilities.fs
 include test/errorreport.fs
 include test/coreexttest.fs
 
+include test/export.fs
+
 report-errors
 report-and-exit

test/export.fs

@@ -0,0 +1,31 @@
+\ planckforth -
+\ Copyright (C) 2021 nineties
+
+testing private and export
+
+: f1 ;
+private{
+
+    : f2 ;
+
+    T{ defined? f1 -> true }T
+    T{ defined? f2 -> true }T
+
+    private{
+
+        : f3 ;
+
+        T{ defined? f2 -> true }T
+        T{ defined? f3 -> true }T
+
+    }private
+
+    T{ defined? f1 -> true }T
+    T{ defined? f2 -> true }T
+    T{ defined? f3 -> false }T
+
+}private
+
+T{ defined? f1 -> true }T
+T{ defined? f2 -> false }T
+T{ defined? f3 -> false }T