Rename "attribute sets" to "sets"

We don't have any other kind of sets so calling them attribute sets is
unnecessarily verbose.

8 files changed, 47 insertions, 54 deletions

diff --git a/src/libexpr/attr-path.cc b/src/libexpr/attr-path.cc
index d834dcae7a..737166435e 100644
--- a/src/libexpr/attr-path.cc
+++ b/src/libexpr/attr-path.cc
@@ -35,15 +35,14 @@ Value * findAlongAttrPath(EvalState & state, const string & attrPath,
         v = vNew;
         state.forceValue(*v);
 
-        /* It should evaluate to either an attribute set or an
-           expression, according to what is specified in the
-           attrPath. */
+        /* It should evaluate to either a set or an expression,
+           according to what is specified in the attrPath. */
 
         if (apType == apAttr) {
 
             if (v->type != tAttrs)
                 throw TypeError(
-                    format("the expression selected by the selection path `%1%' should be an attribute set but is %2%")
+                    format("the expression selected by the selection path `%1%' should be a set but is %2%")
                     % curPath % showType(*v));
 
             Bindings::iterator a = v->attrs->find(state.symbols.create(attr));
diff --git a/src/libexpr/eval-inline.hh b/src/libexpr/eval-inline.hh
index 722273ddad..ec0206eb01 100644
--- a/src/libexpr/eval-inline.hh
+++ b/src/libexpr/eval-inline.hh
@@ -45,7 +45,7 @@ inline void EvalState::forceAttrs(Value & v)
 {
     forceValue(v);
     if (v.type != tAttrs)
-        throwTypeError("value is %1% while an attribute set was expected", showType(v));
+        throwTypeError("value is %1% while a set was expected", showType(v));
 }
 
 
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 29b3e3c828..814c19efcc 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -116,7 +116,7 @@ string showType(const Value & v)
         case tString: return "a string";
         case tPath: return "a path";
         case tNull: return "null";
-        case tAttrs: return "an attribute set";
+        case tAttrs: return "a set";
         case tList: return "a list";
         case tThunk: return "a thunk";
         case tApp: return "a function application";
@@ -488,7 +488,7 @@ inline void EvalState::evalAttrs(Env & env, Expr * e, Value & v)
 {
     e->eval(*this, env, v);
     if (v.type != tAttrs)
-        throwTypeError("value is %1% while an attribute set was expected", showType(v));
+        throwTypeError("value is %1% while a set was expected", showType(v));
 }
 
 
@@ -898,9 +898,8 @@ void ExprOpUpdate::eval(EvalState & state, Env & env, Value & v)
 
     state.mkAttrs(v, v1.attrs->size() + v2.attrs->size());
 
-    /* Merge the attribute sets, preferring values from the second
-       set.  Make sure to keep the resulting vector in sorted
-       order. */
+    /* Merge the sets, preferring values from the second set.  Make
+       sure to keep the resulting vector in sorted order. */
     Bindings::iterator i = v1.attrs->begin();
     Bindings::iterator j = v2.attrs->begin();
 
@@ -1125,8 +1124,7 @@ string EvalState::coerceToString(Value & v, PathSet & context,
 
     if (v.type == tAttrs) {
         Bindings::iterator i = v.attrs->find(sOutPath);
-        if (i == v.attrs->end())
-            throwTypeError("cannot coerce an attribute set (except a derivation) to a string");
+        if (i == v.attrs->end()) throwTypeError("cannot coerce a set to a string");
         return coerceToString(*i->value, context, coerceMore, copyToStore);
     }
 
@@ -1172,9 +1170,8 @@ bool EvalState::eqValues(Value & v1, Value & v2)
     forceValue(v2);
 
     /* !!! Hack to support some old broken code that relies on pointer
-       equality tests between attribute sets.  (Specifically,
-       builderDefs calls uniqList on a list of attribute sets.)  Will
-       remove this eventually. */
+       equality tests between sets.  (Specifically, builderDefs calls
+       uniqList on a list of sets.)  Will remove this eventually. */
     if (&v1 == &v2) return true;
 
     if (v1.type != v2.type) return false;
@@ -1212,8 +1209,8 @@ bool EvalState::eqValues(Value & v1, Value & v2)
             return true;
 
         case tAttrs: {
-            /* If both attribute sets denote a derivation (type =
-               "derivation"), then compare their outPaths. */
+            /* If both sets denote a derivation (type = "derivation"),
+               then compare their outPaths. */
             if (isDerivation(v1) && isDerivation(v2)) {
                 Bindings::iterator i = v1.attrs->find(sOutPath);
                 Bindings::iterator j = v2.attrs->find(sOutPath);
@@ -1263,7 +1260,7 @@ void EvalState::printStats()
     printMsg(v, format("  list concatenations: %1%") % nrListConcats);
     printMsg(v, format("  values allocated: %1% (%2% bytes)")
         % nrValues % (nrValues * sizeof(Value)));
-    printMsg(v, format("  attribute sets allocated: %1%") % nrAttrsets);
+    printMsg(v, format("  sets allocated: %1%") % nrAttrsets);
     printMsg(v, format("  right-biased unions: %1%") % nrOpUpdates);
     printMsg(v, format("  values copied in right-biased unions: %1%") % nrOpUpdateValuesCopied);
     printMsg(v, format("  symbols in symbol table: %1%") % symbols.size());
diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index 8707182ed1..b896137a69 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -19,8 +19,8 @@ class EvalState;
 struct Attr;
 
 
-/* Attribute sets are represented as a vector of attributes, sorted by
-   symbol (i.e. pointer to the attribute name in the symbol table). */
+/* Sets are represented as a vector of attributes, sorted by symbol
+   (i.e. pointer to the attribute name in the symbol table). */
 #if HAVE_BOEHMGC
 typedef std::vector<Attr, gc_allocator<Attr> > BindingsBase;
 #else
diff --git a/src/libexpr/get-drvs.cc b/src/libexpr/get-drvs.cc
index f1cbc0baba..f5d7c189ce 100644
--- a/src/libexpr/get-drvs.cc
+++ b/src/libexpr/get-drvs.cc
@@ -41,7 +41,7 @@ DrvInfo::Outputs DrvInfo::queryOutputs(EvalState & state)
 
             /* For each output... */
             for (unsigned int j = 0; j < i->value->list.length; ++j) {
-                /* Evaluate the corresponding attribute set. */
+                /* Evaluate the corresponding set. */
                 string name = state.forceStringNoCtx(*i->value->list.elems[j]);
                 Bindings::iterator out = attrs->find(state.symbols.create(name));
                 if (out == attrs->end()) continue; // FIXME: throw error?
@@ -119,11 +119,10 @@ void DrvInfo::setMetaInfo(const MetaInfo & meta)
 typedef set<Bindings *> Done;
 
 
-/* Evaluate value `v'.  If it evaluates to an attribute set of type
-   `derivation', then put information about it in `drvs' (unless it's
-   already in `doneExprs').  The result boolean indicates whether it
-   makes sense for the caller to recursively search for derivations in
-   `v'. */
+/* Evaluate value `v'.  If it evaluates to a set of type `derivation',
+   then put information about it in `drvs' (unless it's already in
+   `doneExprs').  The result boolean indicates whether it makes sense
+   for the caller to recursively search for derivations in `v'. */
 static bool getDerivation(EvalState & state, Value & v,
     const string & attrPath, DrvInfos & drvs, Done & done,
     bool ignoreAssertionFailures)
@@ -132,8 +131,8 @@ static bool getDerivation(EvalState & state, Value & v,
         state.forceValue(v);
         if (!state.isDerivation(v)) return true;
 
-        /* Remove spurious duplicates (e.g., an attribute set like
-           `rec { x = derivation {...}; y = x;}'. */
+        /* Remove spurious duplicates (e.g., a set like `rec { x =
+           derivation {...}; y = x;}'. */
         if (done.find(v.attrs) != done.end()) return false;
         done.insert(v.attrs);
 
@@ -218,10 +217,9 @@ static void getDerivations(EvalState & state, Value & vIn,
             if (combineChannels)
                 getDerivations(state, v2, pathPrefix2, autoArgs, drvs, done, ignoreAssertionFailures);
             else if (getDerivation(state, v2, pathPrefix2, drvs, done, ignoreAssertionFailures)) {
-                /* If the value of this attribute is itself an
-                   attribute set, should we recurse into it?  => Only
-                   if it has a `recurseForDerivations = true'
-                   attribute. */
+                /* If the value of this attribute is itself a set,
+                   should we recurse into it?  => Only if it has a
+                   `recurseForDerivations = true' attribute. */
                 if (v2.type == tAttrs) {
                     Bindings::iterator j = v2.attrs->find(state.symbols.create("recurseForDerivations"));
                     if (j != v2.attrs->end() && state.forceBool(*j->value))
diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh
index 2178c016ec..d5d7a02339 100644
--- a/src/libexpr/nixexpr.hh
+++ b/src/libexpr/nixexpr.hh
@@ -123,8 +123,8 @@ struct ExprVar : Expr
        levels up from the current environment and getting the
        `displ'th value in that environment.  In the latter case, the
        value is obtained by getting the attribute named `name' from
-       the attribute set stored in the environment that is `level'
-       levels up from the current one.*/
+       the set stored in the environment that is `level' levels up
+       from the current one.*/
     unsigned int level;
     unsigned int displ;
 
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index badff1ca3f..cfd669d26c 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -103,7 +103,7 @@ static void prim_typeOf(EvalState & state, Value * * args, Value & v)
         case tString: t = "string"; break;
         case tPath: t = "path"; break;
         case tNull: t = "null"; break;
-        case tAttrs: t = "attrs"; break;
+        case tAttrs: t = "set"; break;
         case tList: t = "list"; break;
         case tLambda:
         case tPrimOp:
@@ -729,12 +729,12 @@ static void prim_filterSource(EvalState & state, Value * * args, Value & v)
 
 
 /*************************************************************
- * Attribute sets
+ * Sets
  *************************************************************/
 
 
-/* Return the names of the attributes in an attribute set as a sorted
-   list of strings. */
+/* Return the names of the attributes in a set as a sorted list of
+   strings. */
 static void prim_attrNames(EvalState & state, Value * * args, Value & v)
 {
     state.forceAttrs(*args[0]);
@@ -776,7 +776,7 @@ static void prim_hasAttr(EvalState & state, Value * * args, Value & v)
 }
 
 
-/* Determine whether the argument is an attribute set. */
+/* Determine whether the argument is a set. */
 static void prim_isAttrs(EvalState & state, Value * * args, Value & v)
 {
     state.forceValue(*args[0]);
@@ -807,10 +807,10 @@ static void prim_removeAttrs(EvalState & state, Value * * args, Value & v)
 }
 
 
-/* Builds an attribute set from a list specifying (name, value)
-   pairs.  To be precise, a list [{name = "name1"; value = value1;}
-   ... {name = "nameN"; value = valueN;}] is transformed to {name1 =
-   value1; ... nameN = valueN;}. */
+/* Builds a set from a list specifying (name, value) pairs.  To be
+   precise, a list [{name = "name1"; value = value1;} ... {name =
+   "nameN"; value = valueN;}] is transformed to {name1 = value1;
+   ... nameN = valueN;}. */
 static void prim_listToAttrs(EvalState & state, Value * * args, Value & v)
 {
     state.forceList(*args[0]);
@@ -844,9 +844,9 @@ static void prim_listToAttrs(EvalState & state, Value * * args, Value & v)
 }
 
 
-/* Return the right-biased intersection of two attribute sets as1 and
-   as2, i.e. a set that contains every attribute from as2 that is also
-   a member of as1. */
+/* Return the right-biased intersection of two sets as1 and as2,
+   i.e. a set that contains every attribute from as2 that is also a
+   member of as1. */
 static void prim_intersectAttrs(EvalState & state, Value * * args, Value & v)
 {
     state.forceAttrs(*args[0]);
@@ -1240,7 +1240,7 @@ void EvalState::createBaseEnv()
     addPrimOp("__toFile", 2, prim_toFile);
     addPrimOp("__filterSource", 2, prim_filterSource);
 
-    // Attribute sets
+    // Sets
     addPrimOp("__attrNames", 1, prim_attrNames);
     addPrimOp("__getAttr", 2, prim_getAttr);
     addPrimOp("__hasAttr", 2, prim_hasAttr);
@@ -1290,8 +1290,8 @@ void EvalState::createBaseEnv()
     evalFile(path, v);
     addConstant("derivation", v);
 
-    /* Now that we've added all primops, sort the `builtins' attribute
-       set, because attribute lookups expect it to be sorted. */
+    /* Now that we've added all primops, sort the `builtins' set,
+       because attribute lookups expect it to be sorted. */
     baseEnv.values[0]->attrs->sort();
 }
 
diff --git a/src/libexpr/symbol-table.hh b/src/libexpr/symbol-table.hh
index 9129f0f460..08e31d4965 100644
--- a/src/libexpr/symbol-table.hh
+++ b/src/libexpr/symbol-table.hh
@@ -13,11 +13,10 @@
 namespace nix {
 
 /* Symbol table used by the parser and evaluator to represent and look
-   up identifiers and attribute sets efficiently.
-   SymbolTable::create() converts a string into a symbol.  Symbols
-   have the property that they can be compared efficiently (using a
-   pointer equality test), because the symbol table stores only one
-   copy of each string. */
+   up identifiers and attributes efficiently.  SymbolTable::create()
+   converts a string into a symbol.  Symbols have the property that
+   they can be compared efficiently (using a pointer equality test),
+   because the symbol table stores only one copy of each string. */
 
 class Symbol
 {