1 files changed, 106 insertions, 0 deletions
diff --git a/src/libexpr/value.cc b/src/libexpr/value.cc
new file mode 100644
index 000000000..7e172f989
--- /dev/null
+++ b/src/libexpr/value.cc
@@ -0,0 +1,106 @@
+#include "value.hh"
+
+#include <ostream>
+
+#include "eval.hh"
+#include "print.hh"
+
+
+namespace nix
+{
+
+static void copyContextToValue(Value & v, const NixStringContext & context)
+{
+    if (!context.empty()) {
+        size_t n = 0;
+        v.string.context = gcAllocType<char const *>(context.size() + 1);
+        for (auto & i : context)
+            v.string.context[n++] = gcCopyStringIfNeeded(i.to_string());
+        v.string.context[n] = 0;
+    }
+}
+
+Value::Value(primop_t, PrimOp & primop)
+    : internalType(tPrimOp)
+    , primOp(&primop)
+    , _primop_pad(0)
+{
+    primop.check();
+}
+
+
+void Value::print(EvalState & state, std::ostream & str, PrintOptions options)
+{
+    printValue(state, str, *this, options);
+}
+
+PosIdx Value::determinePos(const PosIdx pos) const
+{
+    // Allow selecting a subset of enum values
+    #pragma GCC diagnostic push
+    #pragma GCC diagnostic ignored "-Wswitch-enum"
+    switch (internalType) {
+        case tAttrs: return attrs->pos;
+        case tLambda: return lambda.fun->pos;
+        case tApp: return app.left->determinePos(pos);
+        default: return pos;
+    }
+    #pragma GCC diagnostic pop
+}
+
+bool Value::isTrivial() const
+{
+    return
+        internalType != tApp
+        && internalType != tPrimOpApp
+        && (internalType != tThunk
+            || (dynamic_cast<ExprAttrs *>(thunk.expr)
+                && static_cast<ExprAttrs *>(thunk.expr)->dynamicAttrs.empty())
+            || dynamic_cast<ExprLambda *>(thunk.expr)
+            || dynamic_cast<ExprList *>(thunk.expr));
+}
+
+PrimOp * Value::primOpAppPrimOp() const
+{
+    Value * left = primOpApp.left;
+    while (left && !left->isPrimOp()) {
+        left = left->primOpApp.left;
+    }
+
+    if (!left)
+        return nullptr;
+    return left->primOp;
+}
+
+void Value::mkPrimOp(PrimOp * p)
+{
+    p->check();
+    clearValue();
+    internalType = tPrimOp;
+    primOp = p;
+}
+
+void Value::mkString(std::string_view s)
+{
+    mkString(gcCopyStringIfNeeded(s));
+}
+
+void Value::mkString(std::string_view s, const NixStringContext & context)
+{
+    mkString(s);
+    copyContextToValue(*this, context);
+}
+
+void Value::mkStringMove(const char * s, const NixStringContext & context)
+{
+    mkString(s);
+    copyContextToValue(*this, context);
+}
+
+
+void Value::mkPath(const SourcePath & path)
+{
+    mkPath(gcCopyStringIfNeeded(path.path.abs()));
+}
+
+}