Lvalue references versus rvalue references — what binds to what?
Every move-semantics question rests on this, and it is where the confusion actually lives. The sharpest part is the bit that sounds like a contradiction: a named rvalue reference is an lvalue.
Exam
Answer these to pass this module.
Start here rather than at the reading. Whatever you miss tells you which part of Learn you actually need — and anything you get right is a part you can skip.
void f(T&& x) { g(x); } — which overload of g is selected?
Which reference can bind to a temporary?
template <class T> void f(T&& x); — what is T&& here?
Explain mode
Lvalue references versus rvalue references — what binds to what?
Explain it in terms of what each reference type can bind to, then say what category the reference variable itself is.
Your own words, two or three sentences, nothing looked up. The rubric unlocks once you submit.
Graded against a set rubric. Three a day on a free account. Need more? Ask on our Facebook page — it's free.
Learn
Lvalues and rvalues, what each reference kind binds to, why a const lvalue reference accepts a temporary, why a named rvalue reference is itself an lvalue, and how a forwarding reference differs despite looking identical.
Ask an AI to teach you this
I'm preparing for a quant developer interview on "Lvalue references versus rvalue references — what binds to what?" Concepts I need to own: lvalues and rvalues, what each reference kind binds to, why a const lvalue reference accepts a temporary, why a named rvalue reference is itself an lvalue, and how a forwarding reference differs despite looking identical. Run this as interview practice, not a lecture. One concept at a time. Wait for my answer before moving on. Per concept: 1. Teach it. Lead with the one-line core claim, then a few short paragraphs. Assume I write C++ but have never had this explained properly. No jargon without defining it. 2. "The 60-second version" — what a strong candidate would SAY out loud. First person, spoken register, no bullets, no headers. That's what I'm rehearsing. 3. Ask me one question that exposes whether I only think I understood it. When I answer, reply in exactly this shape: Verdict: correct / partly correct / wrong — one line on what's wrong. What you missed: only if something's missing. 2-3 sentences. Vocabulary: only if I used a wrong or vague term. Give the right one. Example answer: the model spoken answer, 30 seconds max, first person. More info: define any term I probably don't know, one line each. Follow-up probe: the one question an interviewer asks someone who gave that model answer. Skip any section that doesn't apply. Don't pad. If I'm wrong, say wrong — don't soften it. Do not write my implementation for me. If I ask, refuse and ask what I'd try instead — I need to defend this code with the editor closed.
Do
Ship
Practice with AI
Use these to make the AI your examiner, not your author. If the AI wrote the code, this node doesn't count — you can't defend a design you didn't make.
- P8 — grade my explanation against the rubric, and name what I left out
- P1 — Socratic tutor (refuses to write code)