Simple CASE implementation.

common/all_tests.fs

@@ -18,6 +18,7 @@ needs base_tests.fs
 needs utils_tests.fs
 needs vocabulary_tests.fs
 needs locals_tests.fs
+needs case_tests.fs
 needs doloop_tests.fs
 needs conditionals_tests.fs
 needs float_tests.fs

common/case.fs

@@ -0,0 +1,19 @@
+\ Copyright 2022 Bradley D. Nelson
+\
+\ Licensed under the Apache License, Version 2.0 (the "License");
+\ you may not use this file except in compliance with the License.
+\ You may obtain a copy of the License at
+\
+\     http://www.apache.org/licenses/LICENSE-2.0
+\
+\ Unless required by applicable law or agreed to in writing, software
+\ distributed under the License is distributed on an "AS IS" BASIS,
+\ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+\ See the License for the specific language governing permissions and
+\ limitations under the License.
+
+: CASE ( n -- ) postpone ahead >r postpone begin
+                postpone ahead r> postpone then swap ; immediate
+: ENDCASE   drop postpone drop postpone then ; immediate
+: OF ( n -- ) postpone over postpone = postpone if ; immediate
+: ENDOF   postpone drop over postpone again postpone then ; immediate

common/case_tests.fs

@@ -0,0 +1,48 @@
+\ Copyright 2021 Bradley D. Nelson
+\
+\ Licensed under the Apache License, Version 2.0 (the "License");
+\ you may not use this file except in compliance with the License.
+\ You may obtain a copy of the License at
+\
+\     http://www.apache.org/licenses/LICENSE-2.0
+\
+\ Unless required by applicable law or agreed to in writing, software
+\ distributed under the License is distributed on an "AS IS" BASIS,
+\ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+\ See the License for the specific language governing permissions and
+\ limitations under the License.
+
+( Test CASE Works )
+
+e: test-case
+  : foo
+    case
+      1 of ." one" cr endof
+      2 of ." two" cr endof
+      ." other: " dup . cr
+    endcase
+  ;
+  1 foo
+  out: one
+  2 foo
+  out: two
+  3 foo
+  out: other: 3 
+;e
+
+e: test-case-dup
+  : foo
+    case
+      1 of ." one" cr endof
+      2 of ." two" cr endof
+      1 of ." onemore" cr endof
+      ." other: " dup . cr
+    endcase
+  ;
+  1 foo
+  out: one
+  2 foo
+  out: two
+  3 foo
+  out: other: 3 
+;e

common/forth_namespace_tests.fs

@@ -26,6 +26,13 @@ also internals
     >link
   repeat drop ;
 
+e: check-case
+  out: ENDOF 
+  out: OF 
+  out: ENDCASE 
+  out: CASE 
+;e
+
 e: check-locals
   out: +to 
   out: to 
@@ -507,6 +514,7 @@ e: check-asm
 ;e
 
 e: check-phase2
+  check-case
   check-locals
   check-asm
   check-utils