I want to set first paragraph of text environment to no indentation

Question

I am using evironments to typeset some paragraphs of text with different fonts. I want the first paragraph after \begin{environment} to have no indentation. My code is

 \newenvironment{aut}{\par}{\par}
 \AtBeginEnvironment{aut}{\vspace{\baselineskip}\fontfamily{pzc}\selectfont \par\noindent}

This doesn't have the desired effect, since the first paragraph is indented.

I also tried

    \newenvironment{aut}{\par}{\par}
\AtBeginEnvironment{aut}{\vspace{\baselineskip}\fontfamily{pzc}\selectfont\par\parindent0pt}

but this sets the indent to zero for ALL paragraphs inside the environment, whereas I only want the first paragraph to have no indentation. Any suggestions? Thanks in advance!

Answer 1

It is best to avoid \noindent as it can easily have bad effects if there are blank lines in your source. A list environment allows for specification of variant indents:

\documentclass{article}
\newenvironment{abc}
{\list{}{%
\leftmargin0pt
\itemindent0pt
\listparindent15pt
}\item\relax}{\endlist}
\begin{document}

\noindent X\dotfill X

\begin{abc}
One two three four five one two three four five 
One two three four five one two three four five 
One two three four five one two three four five 

Red yellow green blue red yellow green blue
Red yellow green blue red yellow green blue
Red yellow green blue red yellow green blue
\end{abc}

\begin{abc}
One two three four five one two three four five 
One two three four five one two three four five 
One two three four five one two three four five 

Red yellow green blue red yellow green blue
Red yellow green blue red yellow green blue
Red yellow green blue red yellow green blue
\end{abc}

\end{document}

Answer 2

Based on your approach:

\documentclass{article}
    \usepackage{etoolbox}% needed for \AtBeginEnvironment
    \usepackage{lipsum}
\newenvironment{aut}{\par\hspace*{-\parindent}}{\par}
\AtBeginEnvironment{aut}{\vspace{\baselineskip}\fontfamily{pzc}\selectfont\par} 
\AtEndEnvironment{aut}{\vspace{\baselineskip}}
    \begin{document}
 \lipsum[2]

\begin{aut}\bfseries
    \lipsum[1-2]
\end{aut}
\lipsum[2]
    \end{document}

As cfr said in her comment, you can put content of \AtBeginEnvironment as well \AtEndEnvironment (added by me) into your environment definition.