Create a smart cross-reference to a line in an 'algorithmic' environment using \autoref

Question

To set the name of the \autoref command for an algorithm I use:

\newcommand{\algorithmautorefname}{Algorithm}

like commented here. I would also like to be able to refer to lines within an algorithmic environment with line x.

\begin{algorithm}
\label{alg:myalg}
\begin{algorithmic}[1]
  \State Do X 
  \State Do Y \label{algl:y}
  \State $x = y + z$
\end{algorithmic}
\end{algorithm}

\autoref{alg:myalg} gives me correctly Algorithm 1. In addition, I would also like to have \autoref{algl:y} generate line 2. Until now I'm using: line~\ref{algl:y}.

Seeing the same answer you can define the autoref names by: \....autorefname. But then he mentions that some counters are hidden, for example the line numbering: \c@ALG@line. Is it possible to create an autoref name for them?

I have tried:

\newcommand{\ALGlineautorefname}{line}
\newcommand{\ALG_lineautorefname}{line}
\newcommand{\ALG@lineautorefname}{line}

but none work and only the first compiles.

If possible, how can I create an \autorefname for a line in an algorithmic environment.

Answer 1

The line counter is hidden from hyperref's \autoref because the counter is stepped using \addtocounter{ALG@line}{1} instead of \refstepcounter{ALG@line}. The following patch corrects this, allowing you to define \ALG@lineautorefname:

\documentclass{article}

\usepackage{algorithm,algpseudocode}
\usepackage{hyperref,etoolbox}

\makeatletter
\patchcmd{\ALG@step}{\addtocounter{ALG@line}{1}}{\refstepcounter{ALG@line}}{}{}
\newcommand{\ALG@lineautorefname}{Line}
\makeatother

\newcommand{\algorithmautorefname}{Algorithm}

\begin{document}  

See \autoref{alg:myalg}, specifically \autoref{algl:y}.

\begin{algorithm}
  \caption{An algorithm}\label{alg:myalg}
  \begin{algorithmic}[1]
    \State Do X 
    \State Do Y \label{algl:y}
    \State $x = y + z$
  \end{algorithmic}
\end{algorithm}

\end{document}

Answer 2

The following is a cleveref-based solution. Note: \cref (the main user macro of the cleveref package) works very much like \autoref, except that it's actually far more powerful and flexible than \autoref. For instance, \cref can take multiple arguments; see the code below for an example. Further good news: cleveref is programmed "out of the box" to know that lines in an algorithmic environment should be called, well, "lines" -- no need to provide this setup yourself.

\documentclass{article}
\usepackage{algorithm,algpseudocode}
\usepackage[colorlinks]{hyperref}
\usepackage[noabbrev,capitalize,nameinlink]{cleveref}
\begin{document}

\begin{algorithm}
\caption{Baseline}\label{ALG_baseline}
\begin{algorithmic}[1]
  \State Do X 
  \State Do Y        \label{algl:y}
  \State $x = y + z$ \label{algl:sum}
\end{algorithmic}
\end{algorithm}
\cref{algl:y} in \cref{ALG_baseline} is \dots

\cref{algl:y,algl:sum} of the algorithm are based on \dots
\end{document}