Prefer built-in "nub_left"

Now that justbuild 1.4 is available, the workaround of defining
"nub_left" in terms of "reverse" and "nub_right" is no longer
necessary.

6 files changed, 45 insertions, 89 deletions

diff --git a/CC/RULES b/CC/RULES
index 85c7456..0f1b0ff 100644
--- a/CC/RULES
+++ b/CC/RULES
@@ -99,7 +99,6 @@
     , "base-provides-++": "defaults-base-provides-++"
     , "base-provides-list": "defaults-base-provides-list"
     , "artifacts_list": ["./", "..", "field_artifacts_list"]
-    , "nub_left": ["", "nub_left"]
     , "compile-deps": "compile-deps"
     , "compile-args-deps": "compile-args-deps"
     , "link-deps": "link-deps"
@@ -180,17 +179,14 @@
         ]
       , ["provider", "PATH"]
       , [ "PATH"
-        , { "type": "++"
+        , { "type": "nub_left"
           , "$1":
-            [ {"type": "var", "name": "PATH"}
-            , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-            ]
-          }
-        ]
-      , [ "PATH"
-        , { "type": "let*"
-          , "bindings": [["list", {"type": "var", "name": "PATH"}]]
-          , "body": {"type": "CALL_EXPRESSION", "name": "nub_left"}
+            { "type": "++"
+            , "$1":
+              [ {"type": "var", "name": "PATH"}
+              , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
+              ]
+            }
           }
         ]
       , ["provider", "ENV"]
diff --git a/CC/proto/RULES b/CC/proto/RULES
index 2e4b1d3..07b2dad 100644
--- a/CC/proto/RULES
+++ b/CC/proto/RULES
@@ -83,7 +83,6 @@
     , "base-provides-++": ["./", "..", "defaults-base-provides-++"]
     , "base-provides-list": ["./", "..", "defaults-base-provides-list"]
     , "artifacts_list": ["", "field_artifacts_list"]
-    , "nub_left": ["", "nub_left"]
     , "compile-deps": ["CC", "compile-deps"]
     , "compile-args-deps": ["CC", "compile-args-deps"]
     , "link-deps": ["CC", "link-deps"]
@@ -137,17 +136,14 @@
         ]
       , ["provider", "PATH"]
       , [ "PATH"
-        , { "type": "++"
+        , { "type": "nub_left"
           , "$1":
-            [ {"type": "var", "name": "PATH"}
-            , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-            ]
-          }
-        ]
-      , [ "PATH"
-        , { "type": "let*"
-          , "bindings": [["list", {"type": "var", "name": "PATH"}]]
-          , "body": {"type": "CALL_EXPRESSION", "name": "nub_left"}
+            { "type": "++"
+            , "$1":
+              [ {"type": "var", "name": "PATH"}
+              , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
+              ]
+            }
           }
         ]
       , ["provider", "ENV"]
diff --git a/EXPRESSIONS b/EXPRESSIONS
index 52a381f..b974026 100644
--- a/EXPRESSIONS
+++ b/EXPRESSIONS
@@ -226,18 +226,4 @@
       }
     }
   }
-, "nub_left":
-  { "doc": ["Removes all but the leftmost duplicate from the list."]
-  , "vars": ["list"]
-  , "vars_doc": {"list": ["The list to remove duplicates from."]}
-  , "expression":
-    { "type": "let*"
-    , "bindings":
-      [ ["list", {"type": "reverse", "$1": {"type": "var", "name": "list"}}]
-      , ["list", {"type": "nub_right", "$1": {"type": "var", "name": "list"}}]
-      , ["list", {"type": "reverse", "$1": {"type": "var", "name": "list"}}]
-      ]
-    , "body": {"type": "var", "name": "list"}
-    }
-  }
 }
diff --git a/lint/RULES b/lint/RULES
index e1000d9..0fba127 100644
--- a/lint/RULES
+++ b/lint/RULES
@@ -21,23 +21,17 @@
     { "type": "let*"
     , "bindings":
       [ [ "PATH"
-        , { "type": "reverse"
+        , { "type": "nub_left"
           , "$1":
-            { "type": "nub_right"
+            { "type": "++"
             , "$1":
-              { "type": "reverse"
-              , "$1":
-                { "type": "++"
-                , "$1":
-                  [ {"type": "FIELD", "name": "PATH"}
-                  , { "type": "let*"
-                    , "bindings": [["provider", "PATH"]]
-                    , "body":
-                      {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-                    }
-                  ]
+              [ {"type": "FIELD", "name": "PATH"}
+              , { "type": "let*"
+                , "bindings": [["provider", "PATH"]]
+                , "body":
+                  {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
                 }
-              }
+              ]
             }
           }
         ]
diff --git a/patch/RULES b/patch/RULES
index c55de58..ea495f0 100644
--- a/patch/RULES
+++ b/patch/RULES
@@ -32,7 +32,6 @@
     , "base-provides-++": ["CC", "defaults-base-provides-++"]
     , "base-provides-list": ["CC", "defaults-base-provides-list"]
     , "artifacts_list": ["", "field_artifacts_list"]
-    , "nub_left": ["", "nub_left"]
     , "for host": ["transitions", "for host"]
     }
   , "config_transitions":
@@ -52,17 +51,14 @@
         ]
       , ["provider", "PATH"]
       , [ "PATH"
-        , { "type": "++"
+        , { "type": "nub_left"
           , "$1":
-            [ {"type": "var", "name": "PATH"}
-            , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-            ]
-          }
-        ]
-      , [ "PATH"
-        , { "type": "let*"
-          , "bindings": [["list", {"type": "var", "name": "PATH"}]]
-          , "body": {"type": "CALL_EXPRESSION", "name": "nub_left"}
+            { "type": "++"
+            , "$1":
+              [ {"type": "var", "name": "PATH"}
+              , {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
+              ]
+            }
           }
         ]
       , ["provider", "ENV"]
diff --git a/shell/RULES b/shell/RULES
index 5ac07e6..b9e91bb 100644
--- a/shell/RULES
+++ b/shell/RULES
@@ -116,44 +116,32 @@
           }
         ]
       , [ "PATH"
-        , { "type": "reverse"
+        , { "type": "nub_left"
           , "$1":
-            { "type": "nub_right"
+            { "type": "++"
             , "$1":
-              { "type": "reverse"
-              , "$1":
-                { "type": "++"
-                , "$1":
-                  [ {"type": "FIELD", "name": "PATH"}
-                  , { "type": "let*"
-                    , "bindings": [["provider", "PATH"]]
-                    , "body":
-                      {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-                    }
-                  ]
+              [ {"type": "FIELD", "name": "PATH"}
+              , { "type": "let*"
+                , "bindings": [["provider", "PATH"]]
+                , "body":
+                  {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
                 }
-              }
+              ]
             }
           }
         ]
       , [ "bin dirs"
-        , { "type": "reverse"
+        , { "type": "nub_left"
           , "$1":
-            { "type": "nub_right"
+            { "type": "++"
             , "$1":
-              { "type": "reverse"
-              , "$1":
-                { "type": "++"
-                , "$1":
-                  [ {"type": "FIELD", "name": "bin dirs"}
-                  , { "type": "let*"
-                    , "bindings": [["provider", "bin dirs"]]
-                    , "body":
-                      {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
-                    }
-                  ]
+              [ {"type": "FIELD", "name": "bin dirs"}
+              , { "type": "let*"
+                , "bindings": [["provider", "bin dirs"]]
+                , "body":
+                  {"type": "CALL_EXPRESSION", "name": "base-provides-++"}
                 }
-              }
+              ]
             }
           }
         ]