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authorEelco Dolstra <e.dolstra@tudelft.nl>2010-04-08T11·41+0000
committerEelco Dolstra <e.dolstra@tudelft.nl>2010-04-08T11·41+0000
commitb7b3dd55f9e30e2eccb54aca22830852c5c2b514 (patch)
tree6e4112baf42ab4d330c196d53a147cb6918884da /src
parent7e048eddf55637b9e81d704f6b9f1fdeca98a5ea (diff)
* Remove a lot of dead code.
Diffstat (limited to 'src')
-rw-r--r--src/libexpr/eval.cc500
-rw-r--r--src/libexpr/nixexpr.cc217
-rw-r--r--src/libexpr/nixexpr.hh54
-rw-r--r--src/nix-instantiate/nix-instantiate.cc2
4 files changed, 10 insertions, 763 deletions
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index e72538e60874..2d22a4fdc5c4 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -27,7 +27,14 @@ std::ostream & operator << (std::ostream & str, Value & v)
         str << (v.boolean ? "true" : "false");
         break;
     case tString:
-        str << "\"" << v.string.s << "\""; // !!! escaping
+        str << "\"";
+        for (const char * i = v.string.s; *i; i++)
+            if (*i == '\"' || *i == '\\') str << "\\" << *i;
+            else if (*i == '\n') str << "\\n";
+            else if (*i == '\r') str << "\\r";
+            else if (*i == '\t') str << "\\t";
+            else str << *i;
+        str << "\"";
         break;
     case tPath:
         str << v.path; // !!! escaping?
@@ -930,497 +937,6 @@ bool EvalState::eqValues(Value & v1, Value & v2)
 }
 
 
-#if 0
-/* Pattern-match `pat' against `arg'.  The result is a set of
-   substitutions (`subs') and a set of recursive substitutions
-   (`subsRecursive').  The latter can refer to the variables bound by
-   both `subs' and `subsRecursive'. */
-static void patternMatch(EvalState & state,
-    Pattern pat, Expr arg, ATermMap & subs, ATermMap & subsRecursive)
-{
-    ATerm name;
-    ATermList formals;
-    ATermBool ellipsis;
-    
-    if (matchVarPat(pat, name)) 
-        subs.set(name, arg);
-
-    else if (matchAttrsPat(pat, formals, ellipsis, name)) {
-
-        arg = evalExpr(state, arg);
-
-        if (name != sNoAlias) subs.set(name, arg);
-
-        /* Get the actual arguments. */
-        ATermMap attrs;
-        queryAllAttrs(arg, attrs);
-        unsigned int nrAttrs = attrs.size();
-
-        /* For each formal argument, get the actual argument.  If
-           there is no matching actual argument but the formal
-           argument has a default, use the default. */
-        unsigned int attrsUsed = 0;
-        for (ATermIterator i(formals); i; ++i) {
-            Expr name, def;
-            DefaultValue def2;
-            if (!matchFormal(*i, name, def2)) abort(); /* can't happen */
-
-            Expr value = attrs[name];
-
-            if (value == 0) {
-                if (!matchDefaultValue(def2, def)) def = 0;
-                if (def == 0) throw TypeError(format("the argument named `%1%' required by the function is missing")
-                    % aterm2String(name));
-                subsRecursive.set(name, def);
-            } else {
-                attrsUsed++;
-                attrs.remove(name);
-                subs.set(name, value);
-            }
-
-        }
-
-        /* Check that each actual argument is listed as a formal
-           argument (unless the attribute match specifies a `...'). */
-        if (ellipsis == eFalse && attrsUsed != nrAttrs)
-            throw TypeError(format("the function does not expect an argument named `%1%'")
-                % aterm2String(attrs.begin()->key));
-    }
-
-    else abort();
-}
-
-
-/* Substitute an argument set into the body of a function. */
-static Expr substArgs(EvalState & state,
-    Expr body, Pattern pat, Expr arg)
-{
-    ATermMap subs(16), subsRecursive(16);
-    
-    patternMatch(state, pat, arg, subs, subsRecursive);
-
-    /* If we used any default values, make a recursive attribute set
-       out of the (argument-name, value) tuples.  This is so that we
-       can support default values that refer to each other, e.g.  ({x,
-       y ? x + x}: y) {x = "foo";} evaluates to "foofoo". */
-    if (subsRecursive.size() != 0) {
-        ATermList recAttrs = ATempty;
-        foreach (ATermMap::const_iterator, i, subs)
-            recAttrs = ATinsert(recAttrs, makeBind(i->key, i->value, makeNoPos()));
-        foreach (ATermMap::const_iterator, i, subsRecursive)
-            recAttrs = ATinsert(recAttrs, makeBind(i->key, i->value, makeNoPos()));
-        Expr rec = makeRec(recAttrs, ATempty);
-        foreach (ATermMap::const_iterator, i, subsRecursive)
-            subs.set(i->key, makeSelect(rec, i->key));
-    }
-
-    return substitute(Substitution(0, &subs), body);
-}
-
-
-/* Transform a mutually recursive set into a non-recursive set.  Each
-   attribute is transformed into an expression that has all references
-   to attributes substituted with selection expressions on the
-   original set.  E.g., e = `rec {x = f x y; y = x;}' becomes `{x = f
-   (e.x) (e.y); y = e.x;}'. */
-LocalNoInline(ATerm expandRec(EvalState & state, ATerm e, ATermList rbnds, ATermList nrbnds))
-{
-    ATerm name;
-    Expr e2;
-    Pos pos;
-    Expr eOverrides = 0;
-
-    /* Create the substitution list. */
-    ATermMap subs(ATgetLength(rbnds) + ATgetLength(nrbnds));
-    for (ATermIterator i(rbnds); i; ++i) {
-        if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
-        subs.set(name, makeSelect(e, name));
-    }
-    for (ATermIterator i(nrbnds); i; ++i) {
-        if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
-        if (name == sOverrides) eOverrides = e2;
-        subs.set(name, e2);
-    }
-
-    /* If the rec contains an attribute called `__overrides', then
-       evaluate it, and add the attributes in that set to the rec.
-       This allows overriding of recursive attributes, which is
-       otherwise not possible.  (You can use the // operator to
-       replace an attribute, but other attributes in the rec will
-       still reference the original value, because that value has been
-       substituted into the bodies of the other attributes.  Hence we
-       need __overrides.) */
-    ATermMap overrides;
-    if (eOverrides) {
-        eOverrides = evalExpr(state, eOverrides);
-        queryAllAttrs(eOverrides, overrides, false);
-        foreach (ATermMap::const_iterator, i, overrides)
-            subs.set(i->key, i->value);
-    }
-
-    Substitution subs_(0, &subs);
-
-    /* Create the non-recursive set. */
-    ATermMap as(ATgetLength(rbnds) + ATgetLength(nrbnds));
-    for (ATermIterator i(rbnds); i; ++i) {
-        if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
-        as.set(name, makeAttrRHS(substitute(subs_, e2), pos));
-    }
-
-    if (eOverrides)
-        foreach (ATermMap::const_iterator, i, overrides)
-            as.set(i->key, makeAttrRHS(i->value, makeNoPos()));
-
-    /* Copy the non-recursive bindings.  !!! inefficient */
-    for (ATermIterator i(nrbnds); i; ++i) {
-        if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */
-        as.set(name, makeAttrRHS(e2, pos));
-    }
-
-    return makeAttrs(as);
-}
-
-
-static void flattenList(EvalState & state, Expr e, ATermList & result)
-{
-    ATermList es;
-    e = evalExpr(state, e);
-    if (matchList(e, es))
-        for (ATermIterator i(es); i; ++i)
-            flattenList(state, *i, result);
-    else
-        result = ATinsert(result, e);
-}
-
-
-ATermList flattenList(EvalState & state, Expr e)
-{
-    ATermList result = ATempty;
-    flattenList(state, e, result);
-    return ATreverse(result);
-}
-
-
-/* Evaluation of various language constructs.  These have been taken
-   out of evalExpr2 to reduce stack space usage.  (GCC is really dumb
-   about stack space: it just adds up all the local variables and
-   temporaries of every scope into one huge stack frame.  This is
-   really bad for deeply recursive functions.) */
-
-
-LocalNoInline(Expr evalVar(EvalState & state, ATerm name))
-{
-    ATerm primOp = state.primOps.get(name);
-    if (!primOp)
-        throw EvalError(format("impossible: undefined variable `%1%'") % aterm2String(name));
-    int arity;
-    ATermBlob fun;
-    if (!matchPrimOpDef(primOp, arity, fun)) abort();
-    if (arity == 0)
-        /* !!! backtrace for primop call */
-        return ((PrimOp) ATgetBlobData(fun)) (state, ATermVector());
-    else
-        return makePrimOp(arity, fun, ATempty);
-}
-
-
-LocalNoInline(Expr evalCall(EvalState & state, Expr fun, Expr arg))
-{
-    Pattern pat;
-    ATerm pos;
-    Expr body;
-        
-    /* Evaluate the left-hand side. */
-    fun = evalExpr(state, fun);
-
-    /* Is it a primop or a function? */
-    int arity;
-    ATermBlob funBlob;
-    ATermList args;
-    if (matchPrimOp(fun, arity, funBlob, args)) {
-        args = ATinsert(args, arg);
-        if (ATgetLength(args) == arity) {
-            /* Put the arguments in a vector in reverse (i.e.,
-               actual) order. */
-            ATermVector args2(arity);
-            for (ATermIterator i(args); i; ++i)
-                args2[--arity] = *i;
-            /* !!! backtrace for primop call */
-            return ((PrimOp) ATgetBlobData(funBlob))
-                (state, args2);
-        } else
-            /* Need more arguments, so propagate the primop. */
-            return makePrimOp(arity, funBlob, args);
-    }
-
-    else if (matchFunction(fun, pat, body, pos)) {
-        try {
-            return evalExpr(state, substArgs(state, body, pat, arg));
-        } catch (Error & e) {
-            addErrorPrefix(e, "while evaluating the function at %1%:\n",
-                showPos(pos));
-            throw;
-        }
-    }
-        
-    else throwTypeError(
-        "attempt to call something which is neither a function nor a primop (built-in operation) but %1%",
-        showType(fun));
-}
-
-
-LocalNoInline(Expr evalWith(EvalState & state, Expr defs, Expr body, ATerm pos))
-{
-    ATermMap attrs;
-    try {
-        defs = evalExpr(state, defs);
-        queryAllAttrs(defs, attrs);
-    } catch (Error & e) {
-        addErrorPrefix(e, "while evaluating the `with' definitions at %1%:\n",
-            showPos(pos));
-        throw;
-    }
-    try {
-        body = substitute(Substitution(0, &attrs), body);
-        checkVarDefs(state.primOps, body);
-        return evalExpr(state, body);
-    } catch (Error & e) {
-        addErrorPrefix(e, "while evaluating the `with' body at %1%:\n",
-            showPos(pos));
-        throw;
-    } 
-}
-
-
-/* Implementation of the `==' and `!=' operators. */
-LocalNoInline(bool areEqual(EvalState & state, Expr e1, Expr e2))
-{
-    e1 = evalExpr(state, e1);
-    e2 = evalExpr(state, e2);
-
-    /* We cannot test functions/primops for equality, and we currently
-       don't support testing equality between attribute sets or lists
-       - that would have to be a deep equality test to be sound. */
-    AFun sym1 = ATgetAFun(e1);
-    AFun sym2 = ATgetAFun(e2);
-
-    if (sym1 != sym2) return false;
-
-    /* Functions are incomparable. */
-    if (sym1 == symFunction || sym1 == symPrimOp) return false;
-
-    if (!state.allowUnsafeEquality && sym1 == symAttrs)
-        throw EvalError("comparison of attribute sets is not implemented");
-
-    /* !!! This allows comparisons of infinite data structures to
-       succeed, such as `let x = [x]; in x == x'.  This is
-       undesirable, since equivalent (?) terms such as `let x = [x]; y
-       = [y]; in x == y' don't terminate. */
-    if (e1 == e2) return true;
-    
-    if (sym1 == symList) {
-        ATermList es1; matchList(e1, es1);
-        ATermList es2; matchList(e2, es2);
-        if (ATgetLength(es1) != ATgetLength(es2)) return false;
-        ATermIterator i(es1), j(es2);
-        while (*i) {
-            if (!areEqual(state, *i, *j)) return false;
-            ++i; ++j;
-        }
-        return true;
-    }
-    
-    return false;
-}
-
-
-Expr evalExpr2(EvalState & state, Expr e)
-{
-    /* When changing this function, make sure that you don't cause a
-       (large) increase in stack consumption! */
-    
-    char x;
-    if (&x < deepestStack) deepestStack = &x;
-    
-    Expr e1, e2, e3;
-    ATerm name, pos;
-    AFun sym = ATgetAFun(e);
-
-    /* Normal forms. */
-    if (sym == symStr ||
-        sym == symPath ||
-        sym == symNull ||
-        sym == symInt ||
-        sym == symBool ||
-        sym == symFunction ||
-        sym == symAttrs ||
-        sym == symList ||
-        sym == symPrimOp)
-        return e;
-    
-    /* The `Closed' constructor is just a way to prevent substitutions
-       into expressions not containing free variables. */
-    if (matchClosed(e, e1))
-        return evalExpr(state, e1);
-
-    /* Any encountered variables must be primops (since undefined
-       variables are detected after parsing). */
-    if (matchVar(e, name)) return evalVar(state, name);
-
-    /* Function application. */
-    if (matchCall(e, e1, e2)) return evalCall(state, e1, e2);
-
-    /* Attribute selection. */
-    if (matchSelect(e, e1, name)) return evalSelect(state, e1, name);
-
-    /* Mutually recursive sets. */
-    ATermList rbnds, nrbnds;
-    if (matchRec(e, rbnds, nrbnds))
-        return expandRec(state, e, rbnds, nrbnds);
-
-    /* Conditionals. */
-    if (matchIf(e, e1, e2, e3))
-        return evalExpr(state, evalBool(state, e1) ? e2 : e3);
-
-    /* Assertions. */
-    if (matchAssert(e, e1, e2, pos)) return evalAssert(state, e1, e2, pos);
-
-    /* Withs. */
-    if (matchWith(e, e1, e2, pos)) return evalWith(state, e1, e2, pos);
-
-    /* Generic equality/inequality.  Note that the behaviour on
-       composite data (lists, attribute sets) and functions is
-       undefined, since the subterms of those terms are not evaluated.
-       However, we don't want to make (==) strict, because that would
-       make operations like `big_derivation == null' very slow (unless
-       we were to evaluate them side-by-side). */
-    if (matchOpEq(e, e1, e2)) return makeBool(areEqual(state, e1, e2));
-        
-    if (matchOpNEq(e, e1, e2)) return makeBool(!areEqual(state, e1, e2));
-        
-    /* Negation. */
-    if (matchOpNot(e, e1))
-        return makeBool(!evalBool(state, e1));
-
-    /* Implication. */
-    if (matchOpImpl(e, e1, e2))
-        return makeBool(!evalBool(state, e1) || evalBool(state, e2));
-
-    /* Conjunction (logical AND). */
-    if (matchOpAnd(e, e1, e2))
-        return makeBool(evalBool(state, e1) && evalBool(state, e2));
-
-    /* Disjunction (logical OR). */
-    if (matchOpOr(e, e1, e2))
-        return makeBool(evalBool(state, e1) || evalBool(state, e2));
-
-    /* Attribute set update (//). */
-    if (matchOpUpdate(e, e1, e2))
-        return updateAttrs(evalExpr(state, e1), evalExpr(state, e2));
-
-    /* Attribute existence test (?). */
-    if (matchOpHasAttr(e, e1, name)) return evalHasAttr(state, e1, name);
-
-    /* String or path concatenation. */
-    if (sym == symOpPlus || sym == symConcatStrings)
-        return evalPlusConcat(state, e);
-
-    /* Backwards compatability: subpath operator (~). */
-    if (matchSubPath(e, e1, e2)) return evalSubPath(state, e1, e2);
-
-    /* List concatenation. */
-    if (matchOpConcat(e, e1, e2)) return evalOpConcat(state, e1, e2);
-
-    /* Barf. */
-    abort();
-}
-
-
-Expr evalExpr(EvalState & state, Expr e)
-{
-    checkInterrupt();
-
-#if 0
-    startNest(nest, lvlVomit,
-        format("evaluating expression: %1%") % e);
-#endif
-
-    state.nrEvaluated++;
-
-    /* Consult the memo table to quickly get the normal form of
-       previously evaluated expressions. */
-    Expr nf = state.normalForms.get(e);
-    if (nf) {
-        if (nf == makeBlackHole())
-            throwEvalError("infinite recursion encountered");
-        state.nrCached++;
-        return nf;
-    }
-
-    /* Otherwise, evaluate and memoize. */
-    state.normalForms.set(e, makeBlackHole());
-    try {
-        nf = evalExpr2(state, e);
-    } catch (Error & err) {
-        state.normalForms.remove(e);
-        throw;
-    }
-    state.normalForms.set(e, nf);
-    return nf;
-}
-
-
-static Expr strictEvalExpr(EvalState & state, Expr e, ATermMap & nfs);
-
-
-static Expr strictEvalExpr_(EvalState & state, Expr e, ATermMap & nfs)
-{
-    e = evalExpr(state, e);
-
-    ATermList as;
-    if (matchAttrs(e, as)) {
-        ATermList as2 = ATempty;
-        for (ATermIterator i(as); i; ++i) {
-            ATerm name; Expr e; ATerm pos;
-            if (!matchBind(*i, name, e, pos)) abort(); /* can't happen */
-            as2 = ATinsert(as2, makeBind(name, strictEvalExpr(state, e, nfs), pos));
-        }
-        return makeAttrs(ATreverse(as2));
-    }
-    
-    ATermList es;
-    if (matchList(e, es)) {
-        ATermList es2 = ATempty;
-        for (ATermIterator i(es); i; ++i)
-            es2 = ATinsert(es2, strictEvalExpr(state, *i, nfs));
-        return makeList(ATreverse(es2));
-    }
-    
-    return e;
-}
-
-
-static Expr strictEvalExpr(EvalState & state, Expr e, ATermMap & nfs)
-{
-    Expr nf = nfs.get(e);
-    if (nf) return nf;
-
-    nf = strictEvalExpr_(state, e, nfs);
-
-    nfs.set(e, nf);
-    
-    return nf;
-}
-
-
-Expr strictEvalExpr(EvalState & state, Expr e)
-{
-    ATermMap strictNormalForms;
-    return strictEvalExpr(state, e, strictNormalForms);
-}
-#endif
-
-
 void EvalState::printStats()
 {
     char x;
diff --git a/src/libexpr/nixexpr.cc b/src/libexpr/nixexpr.cc
index e581b1329c88..3c5d02b34f66 100644
--- a/src/libexpr/nixexpr.cc
+++ b/src/libexpr/nixexpr.cc
@@ -52,50 +52,6 @@ ATerm bottomupRewrite(TermFun & f, ATerm e)
 }
 
 
-void queryAllAttrs(Expr e, ATermMap & attrs, bool withPos)
-{
-    ATermList bnds;
-    if (!matchAttrs(e, bnds))
-        throw TypeError(format("value is %1% while an attribute set was expected") % showType(e));
-
-    for (ATermIterator i(bnds); i; ++i) {
-        ATerm name;
-        Expr e;
-        ATerm pos;
-        if (!matchBind(*i, name, e, pos)) abort(); /* can't happen */
-        attrs.set(name, withPos ? makeAttrRHS(e, pos) : e);
-    }
-}
-
-
-Expr queryAttr(Expr e, const string & name)
-{
-    ATerm dummy;
-    return queryAttr(e, name, dummy);
-}
-
-
-Expr queryAttr(Expr e, const string & name, ATerm & pos)
-{
-    ATermList bnds;
-    if (!matchAttrs(e, bnds))
-        throw TypeError(format("value is %1% while an attribute set was expected") % showType(e));
-
-    for (ATermIterator i(bnds); i; ++i) {
-        ATerm name2, pos2;
-        Expr e;
-        if (!matchBind(*i, name2, e, pos2))
-            abort(); /* can't happen */
-        if (aterm2String(name2) == name) {
-            pos = pos2;
-            return e;
-        }
-    }
-
-    return 0;
-}
-
-
 Expr makeAttrs(const ATermMap & attrs)
 {
     ATermList bnds = ATempty;
@@ -131,88 +87,6 @@ static void varsBoundByPattern(ATermMap & map, Pattern pat)
 }
 
 
-Expr substitute(const Substitution & subs, Expr e)
-{
-    checkInterrupt();
-
-    //if (subs.size() == 0) return e;
-
-    ATerm name, pos, e2;
-
-    /* As an optimisation, don't substitute in subterms known to be
-       closed. */
-    if (matchClosed(e, e2)) return e;
-
-    if (matchVar(e, name)) {
-        Expr sub = subs.lookup(name);
-        if (sub == makeRemoved()) sub = 0;
-        Expr wrapped;
-        /* Add a "closed" wrapper around terms that aren't already
-           closed.  The check is necessary to prevent repeated
-           wrapping, e.g., closed(closed(closed(...))), which kills
-           caching. */
-        return sub ? (matchClosed(sub, wrapped) ? sub : makeClosed(sub)) : e;
-    }
-
-    /* In case of a function, filter out all variables bound by this
-       function. */
-    Pattern pat;
-    ATerm body;
-    if (matchFunction(e, pat, body, pos)) {
-        ATermMap map(16);
-        varsBoundByPattern(map, pat);
-        Substitution subs2(&subs, &map);
-        return makeFunction(
-            (Pattern) substitute(subs2, (Expr) pat),
-            substitute(subs2, body), pos);
-    }
-
-    /* Idem for a mutually recursive attribute set. */
-    ATermList rbnds, nrbnds;
-    if (matchRec(e, rbnds, nrbnds)) {
-        ATermMap map(ATgetLength(rbnds) + ATgetLength(nrbnds));
-        for (ATermIterator i(rbnds); i; ++i)
-            if (matchBind(*i, name, e2, pos)) map.set(name, makeRemoved());
-            else abort(); /* can't happen */
-        for (ATermIterator i(nrbnds); i; ++i)
-            if (matchBind(*i, name, e2, pos)) map.set(name, makeRemoved());
-            else abort(); /* can't happen */
-        return makeRec(
-            (ATermList) substitute(Substitution(&subs, &map), (ATerm) rbnds),
-            (ATermList) substitute(subs, (ATerm) nrbnds));
-    }
-
-    if (ATgetType(e) == AT_APPL) {
-        AFun fun = ATgetAFun(e);
-        int arity = ATgetArity(fun);
-        ATerm args[arity];
-        bool changed = false;
-
-        for (int i = 0; i < arity; ++i) {
-            ATerm arg = ATgetArgument(e, i);
-            args[i] = substitute(subs, arg);
-            if (args[i] != arg) changed = true;
-        }
-        
-        return changed ? (ATerm) ATmakeApplArray(fun, args) : e;
-    }
-
-    if (ATgetType(e) == AT_LIST) {
-        unsigned int len = ATgetLength((ATermList) e);
-        ATerm es[len];
-        ATermIterator i((ATermList) e);
-        for (unsigned int j = 0; i; ++i, ++j)
-            es[j] = substitute(subs, *i);
-        ATermList out = ATempty;
-        for (unsigned int j = len; j; --j)
-            out = ATinsert(out, es[j - 1]);
-        return (ATerm) out;
-    }
-
-    return e;
-}
-
-
 /* We use memoisation to prevent exponential complexity on heavily
    shared ATerms (remember, an ATerm is a graph, not a tree!).  Note
    that using an STL set is fine here wrt to ATerm garbage collection
@@ -287,51 +161,6 @@ void checkVarDefs(const ATermMap & defs, Expr e)
 }
 
 
-struct Canonicalise : TermFun
-{
-    ATerm operator () (ATerm e)
-    {
-        /* Remove position info. */
-        ATerm path;
-        int line, column;
-        if (matchPos(e, path, line, column))
-            return makeNoPos();
-
-        /* Sort attribute sets. */
-        ATermList _;
-        if (matchAttrs(e, _)) {
-            ATermMap attrs;
-            queryAllAttrs(e, attrs);
-            StringSet names;
-            for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i)
-                names.insert(aterm2String(i->key));
-
-            ATermList attrs2 = ATempty;
-            for (StringSet::reverse_iterator i = names.rbegin(); i != names.rend(); ++i)
-                attrs2 = ATinsert(attrs2,
-                    makeBind(toATerm(*i), attrs.get(toATerm(*i)), makeNoPos()));
-
-            return makeAttrs(attrs2);
-        }
-        
-        return e;
-    }
-};
-
-
-Expr canonicaliseExpr(Expr e)
-{
-    Canonicalise canonicalise;
-    return bottomupRewrite(canonicalise, e);
-}
-
-
-Expr makeBool(bool b)
-{
-    return b ? eTrue : eFalse;
-}
-
-
 bool matchStr(Expr e, string & s, PathSet & context)
 {
     ATermList l;
@@ -354,50 +183,4 @@ Expr makeStr(const string & s, const PathSet & context)
 }
 
 
-string showType(Expr e)
-{
-    ATerm t1, t2;
-    ATermList l1;
-    ATermBlob b1;
-    int i1;
-    Pattern p1;
-    if (matchStr(e, t1, l1)) return "a string";
-    if (matchPath(e, t1)) return "a path";
-    if (matchNull(e)) return "null";
-    if (matchInt(e, i1)) return "an integer";
-    if (matchBool(e, t1)) return "a boolean";
-    if (matchFunction(e, p1, t1, t2)) return "a function";
-    if (matchAttrs(e, l1)) return "an attribute set";
-    if (matchList(e, l1)) return "a list";
-    if (matchPrimOp(e, i1, b1, l1)) return "a partially applied built-in function";
-    return "an unknown type";
-}
-
-
-string showValue(Expr e)
-{
-    PathSet context;
-    string s;
-    ATerm s2;
-    int i;
-    if (matchStr(e, s, context)) {
-        string u;
-        for (string::iterator i = s.begin(); i != s.end(); ++i)
-            if (*i == '\"' || *i == '\\') u += "\\" + *i;
-            else if (*i == '\n') u += "\\n";
-            else if (*i == '\r') u += "\\r";
-            else if (*i == '\t') u += "\\t";
-            else u += *i;
-        return "\"" + u + "\"";
-    }
-    if (matchPath(e, s2)) return aterm2String(s2);
-    if (matchNull(e)) return "null";
-    if (matchInt(e, i)) return (format("%1%") % i).str();
-    if (e == eTrue) return "true";
-    if (e == eFalse) return "false";
-    /* !!! incomplete */
-    return "<unknown>";
-}
-
- 
 }
diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh
index c7cdf46df974..9f1050d807d4 100644
--- a/src/libexpr/nixexpr.hh
+++ b/src/libexpr/nixexpr.hh
@@ -34,34 +34,10 @@ typedef ATerm ATermBool;
 typedef vector<ATerm> ATermVector;
 
 
-/* A substitution is a linked list of ATermMaps that map names to
-   identifiers.  We use a list of ATermMaps rather than a single to
-   make it easy to grow or shrink a substitution when entering a
-   scope. */
-struct Substitution
-{
-    ATermMap * map;
-    const Substitution * prev;
-
-    Substitution(const Substitution * prev, ATermMap * map)
-    {
-        this->prev = prev;
-        this->map = map;
-    }
-    
-    Expr lookup(Expr name) const
-    {
-        Expr x;
-        for (const Substitution * s(this); s; s = s->prev)
-            if ((x = s->map->get(name))) return x;
-        return 0;
-    }
-};
-
-
 /* Show a position. */
 string showPos(ATerm pos);
 
+
 /* Generic bottomup traversal over ATerms.  The traversal first
    recursively descends into subterms, and then applies the given term
    function to the resulting term. */
@@ -73,37 +49,15 @@ struct TermFun
 ATerm bottomupRewrite(TermFun & f, ATerm e);
 
 
-/* Query all attributes in an attribute set expression.  The
-   expression must be in normal form. */
-void queryAllAttrs(Expr e, ATermMap & attrs, bool withPos = false);
-
-/* Query a specific attribute from an attribute set expression.  The
-   expression must be in normal form. */
-Expr queryAttr(Expr e, const string & name);
-Expr queryAttr(Expr e, const string & name, ATerm & pos);
-
 /* Create an attribute set expression from an Attrs value. */
 Expr makeAttrs(const ATermMap & attrs);
 
 
-/* Perform a set of substitutions on an expression. */
-Expr substitute(const Substitution & subs, Expr e);
-
-
 /* Check whether all variables are defined in the given expression.
    Throw an exception if this isn't the case. */
 void checkVarDefs(const ATermMap & def, Expr e);
 
 
-/* Canonicalise a Nix expression by sorting attributes and removing
-   location information. */
-Expr canonicaliseExpr(Expr e);
-
-
-/* Create an expression representing a boolean. */
-Expr makeBool(bool b);
-
-
 /* Manipulation of Str() nodes.  Note: matchStr() does not clear
    context!  */
 bool matchStr(Expr e, string & s, PathSet & context);
@@ -111,12 +65,6 @@ bool matchStr(Expr e, string & s, PathSet & context);
 Expr makeStr(const string & s, const PathSet & context = PathSet());
 
 
-/* Showing types, values. */
-string showType(Expr e);
-
-string showValue(Expr e);
-
- 
 }
 
 
diff --git a/src/nix-instantiate/nix-instantiate.cc b/src/nix-instantiate/nix-instantiate.cc
index ac405aa6601c..7931af6abd02 100644
--- a/src/nix-instantiate/nix-instantiate.cc
+++ b/src/nix-instantiate/nix-instantiate.cc
@@ -42,7 +42,7 @@ void processExpr(EvalState & state, const Strings & attrPaths,
     bool evalOnly, bool xmlOutput, Expr e)
 {
     if (parseOnly)
-        std::cout << format("%1%\n") % canonicaliseExpr(e);
+        std::cout << format("%1%\n");
     else
         foreach (Strings::const_iterator, i, attrPaths) {
             Value v;