Merge remote-tracking branch 'origin/master' into fix_definition_autoload_to_builtin

Author: mmatera

CHANGES.rst

@@ -17,6 +17,7 @@ New Builtins
 #. ``Curl`` (2-D and 3-D vector forms only)
 #. ``Kurtosis``
 #. ``PauliMatrix``
+#. ``Remove``
 #. ``SetOptions``
 #. ``SixJSymbol``
 #. ``Skewness``

SYMBOLS_MANIFEST.txt

@@ -831,6 +831,7 @@ System`RegularExpression
 System`RegularPolygon
 System`RegularPolygonBox
 System`ReleaseHold
+System`Remove
 System`RemoveDiacritics
 System`RenameDirectory
 System`RenameFile
@@ -877,6 +878,7 @@ System`SetAttributes
 System`SetDelayed
 System`SetDirectory
 System`SetFileDate
+System`SetOptions
 System`SetStreamPosition
 System`Share
 System`Sharpen

mathics/builtin/assignments/clear.py

@@ -39,6 +39,10 @@
 
 class Clear(Builtin):
     """
+    <url>
+    :WMA link:
+    https://reference.wolfram.com/language/ref/Clear.html</url>
+
     <dl>
       <dt>'Clear[$symb1$, $symb2$, ...]'
       <dd>clears all values of the given symbols. The arguments can also be given as strings containing symbol names.
@@ -77,7 +81,6 @@ class Clear(Builtin):
     allow_locked = True
     attributes = A_HOLD_ALL | A_PROTECTED
     messages = {
-        "ssym": "`1` is not a symbol or a string.",
         "spsym": "Special symbol `1` cannot be cleared.",
     }
     summary_text = "clear all values associated with the LHS or symbol"
@@ -135,6 +138,10 @@ def apply(self, symbols, evaluation):
 
 class ClearAll(Clear):
     """
+    <url>
+    :WMA link:
+    https://reference.wolfram.com/language/ref/ClearAll.html</url>
+
     <dl>
       <dt>'ClearAll[$symb1$, $symb2$, ...]'
       <dd>clears all values, attributes, messages and options associated with the given symbols.
@@ -167,12 +174,50 @@ def do_clear(self, definition):
         definition.defaultvalues = []
 
 
+class Remove(Builtin):
+    """
+    <url>
+    :WMA link:
+    https://reference.wolfram.com/language/ref/Remove.html</url>
+
+    <dl>
+      <dt>'Remove[$x$]'
+      <dd>removes the definition associated to $x$.
+    </dl>
+    >> a := 2
+    >> Names["Global`a"]
+     = {a}
+    >> Remove[a]
+    >> Names["Global`a"]
+     = {}
+    """
+
+    attributes = A_HOLD_ALL | A_LOCKED | A_PROTECTED
+
+    precedence = 670
+    summary_text = "remove the definition of a symbol"
+
+    def eval(self, symb, evaluation):
+        """Remove[symb_]"""
+        if isinstance(symb, Symbol):
+            evaluation.definitions.reset_user_definition(symb.name)
+        elif isinstance(symb, String):
+            evaluation.definitions.reset_user_definition(symb.value)
+        else:
+            evaluation.message(self.get_name(), "ssym", symb)
+        return SymbolNull
+
+
 class Unset(PostfixOperator):
     """
+    <url>
+    :WMA link:
+    https://reference.wolfram.com/language/ref/Unset.html</url>
+
     <dl>
-    <dt>'Unset[$x$]'
-    <dt>'$x$=.'
-        <dd>removes any value belonging to $x$.
+      <dt>'Unset[$x$]'
+      <dt>'$x$=.'
+      <dd>removes any value belonging to $x$.
     </dl>
     >> a = 2
      = 2

mathics/builtin/attributes.py

@@ -205,9 +205,6 @@ class Protect(Builtin):
     """
 
     attributes = A_HOLD_ALL | A_PROTECTED
-    messages = {
-        "ssym": "`1` is not a symbol or a string.",
-    }
     summary_text = "protect a symbol against redefinitions"
 
     def apply(self, symbols, evaluation):
@@ -261,9 +258,6 @@ class Unprotect(Builtin):
     """
 
     attributes = A_HOLD_ALL | A_PROTECTED
-    messages = {
-        "ssym": "`1` is not a symbol or a string.",
-    }
     summary_text = "remove protection against redefinitions"
 
     def apply(self, symbols, evaluation):

mathics/builtin/messages.py

@@ -603,6 +603,7 @@ class General(Builtin):
         "argtu": ("`1` called with 1 argument; `2` or `3` arguments are expected."),
         "base": "Requested base `1` in `2` should be between 2 and `3`.",
         "boxfmt": "`1` is not a box formatting type.",
+        "charcode": "The character encoding `1` is not supported. Use $CharacterEncodings to list supported encodings.",
         "color": "`1` is not a valid color or gray-level specification.",
         "cxt": "`1` is not a valid context name.",
         "divz": "The argument `1` should be nonzero.",
@@ -645,18 +646,19 @@ class General(Builtin):
         "setp": "Part assignment to `1` could not be made",
         "setps": "`1` in the part assignment is not a symbol.",
         "span": "`1` is not a valid Span specification.",
+        "ssym": "`1` is not a symbol or a string.",
         "stream": "`1` is not string, InputStream[], or OutputStream[]",
         "string": "String expected.",
         "sym": "Argument `1` at position `2` is expected to be a symbol.",
         "tag": "Rule for `1` can only be attached to `2`.",
         "take": "Cannot take positions `1` through `2` in `3`.",
+        "ucdec": "An invalid unicode sequence was encountered and ignored.",
         "vrule": (
             "Cannot set `1` to `2`, " "which is not a valid list of replacement rules."
         ),
         "write": "Tag `1` in `2` is Protected.",
         "wrsym": "Symbol `1` is Protected.",
-        "ucdec": "An invalid unicode sequence was encountered and ignored.",
-        "charcode": "The character encoding `1` is not supported. Use $CharacterEncodings to list supported encodings.",
+        # TODO: someone please explain why these are different...
         # Self-defined messages
         "rep": "`1` is not a valid replacement rule.",
         "options": "`1` is not a valid list of option rules.",