libexpr/value/print.* -> libexpr/print.*

Generalizes the file to sensibly allow printing any part of the
language syntax.

1 files changed, 28 insertions, 0 deletions

diff --git a/src/libexpr/print.cc b/src/libexpr/print.cc
new file mode 100644
index 000000000..282903b72
--- /dev/null
+++ b/src/libexpr/print.cc
@@ -0,0 +1,28 @@
+#include "print.hh"
+
+namespace nix {
+
+std::ostream &
+printLiteralString(std::ostream & str, const std::string_view string)
+{
+    str << "\"";
+    for (auto i = string.begin(); i != string.end(); ++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 if (*i == '$' && *(i+1) == '{') str << "\\" << *i;
+        else str << *i;
+    }
+    str << "\"";
+    return str;
+}
+
+std::ostream &
+printLiteralBool(std::ostream & str, bool boolean)
+{
+    str << (boolean ? "true" : "false");
+    return str;
+}
+
+}