Exception is thrown when a string containing 'less than' sign (<) is passed from controller to blade .

[dhruva81]

Hi @ismaelw

The package is throwing exception when we pass a string containing 'less than ' character (<) from controller to blade tex file.

Kindly check following controller and blade files. These are not working and exception is thrown.

Controller

     public function laratex()
      {
            $data = "$ (a < b) $";

            return (new LaraTeX('tex'))->with([
                        'data' => $data,
                  ])->download( 'test.pdf');
      }

Blade

\documentclass[a4paper,9pt,landscape]{article}

\usepackage{adjustbox}
\usepackage[english]{babel}
\usepackage[scaled=.92]{helvet}
\usepackage{fancyhdr}
\usepackage[svgnames,table]{xcolor}
\usepackage[a4paper,inner=1.5cm,outer=1.5cm,top=1cm,bottom=1cm,bindingoffset=0cm]{geometry}
\usepackage{blindtext}
\geometry{textwidth=\paperwidth, textheight=\paperheight, noheadfoot, nomarginpar}

\renewcommand{\familydefault}{\sfdefault}

\pagestyle{fancy}
\fancyhead{}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\fancyfoot[LE,RO]{\thepage}

\fancyfoot[C]{\fontsize{8pt}{8pt}\selectfont Above document is auto-generated.}
\renewcommand{\footrulewidth}{0.2pt}


\begin{document}
 
      {{  $data }}

\end{document}

Exception

Ismaelw\LaraTeX\LaratexException


Misplaced alignment tab character &. l.27 $a & lt; b$ ? ! Emergency stop. l.27 $a & lt; b$ ! ==> Fatal error occurred, no output PDF file produced! 

Ismaelw\LaraTeX\LaraTeX::parseError

But if I use 'less than' symbol (<) directly in blade, then it is working fine and PDF is generating.

For example - below code is working fine

Controller

  public function raw()
  {
           return (new LaraTeX('tex'))->download( 'test.pdf');
  }

Blade

\documentclass[a4paper,9pt,landscape]{article}

\usepackage{adjustbox}
\usepackage[english]{babel}
\usepackage[scaled=.92]{helvet}
\usepackage{fancyhdr}
\usepackage[svgnames,table]{xcolor}
\usepackage[a4paper,inner=1.5cm,outer=1.5cm,top=1cm,bottom=1cm,bindingoffset=0cm]{geometry}
\usepackage{blindtext}
\geometry{textwidth=\paperwidth, textheight=\paperheight, noheadfoot, nomarginpar}

\renewcommand{\familydefault}{\sfdefault}

\pagestyle{fancy}
\fancyhead{}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\fancyfoot[LE,RO]{\thepage}

\fancyfoot[C]{\fontsize{8pt}{8pt}\selectfont Above document is auto-generated.}
\renewcommand{\footrulewidth}{0.2pt}


\begin{document}
 
   $ a < b $

\end{document}

Kindly help, how can I pass string containing less than sign (<) from controller to blade and render them in PDF.

Thank you

[ismaelw]

Hi @dhruva81

Thank you so much for your message and sharing your issue.
Please give me some time so I can look into it.

If you already have an idea yourself on where the issue could be I am more than happy to hear.

Kind regards,
Ismael

[ismaelw]

Hi @dhruva81

I created a test environment myself and tried everything the way you did.
In my case I had another issue that is basically the same like yours but at another location.

As far as I can reproduce and analyze it, the issue is with how Laravel Blade works. In Blade Templating {{ }} statements are automatically converted with the PHP Function htmlspecialchars() to prevent XSS attacks. So your special characters get converted like this: & = & and < = &lt;. This makes pdflatex fail when rendering.

To fix that issue you would need laravels builtin {!! !!} statement to get unescaped data written to your tex template.

So in your case it would look like this:

\documentclass[a4paper,9pt,landscape]{article}

\usepackage{adjustbox}
\usepackage[english]{babel}
\usepackage[scaled=.92]{helvet}
\usepackage{fancyhdr}
\usepackage[svgnames,table]{xcolor}
\usepackage[a4paper,inner=1.5cm,outer=1.5cm,top=1cm,bottom=1cm,bindingoffset=0cm]{geometry}
\usepackage{blindtext}
\geometry{textwidth=\paperwidth, textheight=\paperheight, noheadfoot, nomarginpar}

\renewcommand{\familydefault}{\sfdefault}

\pagestyle{fancy}
\fancyhead{}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\fancyfoot[LE,RO]{\thepage}

\fancyfoot[C]{\fontsize{8pt}{8pt}\selectfont Above document is auto-generated.}
\renewcommand{\footrulewidth}{0.2pt}


\begin{document}
 
      {!! $data !!}

\end{document}

Please check this solution in your environment and please also tell me if it fixes your issue :)

Kind regards,
Ismael

[ismaelw]

Hi @dhruva81

As soon as you have been able to check the solution above, I am happy to get some feedback.
If you need any further assistance do not hesitate to contact me :)

Kind regards,
Ismael

[dhruva81]

Hi @ismaelw

Thank you for your reply.

I have tried using solution provided by you and it is working fine :)

\begin{document}
 
      {!! $data !!}

\end{document}

Thank you very much 👍 💯

[ismaelw]

Hi @dhruva81

Thank you so much for your reply.
I will mark this issue as closed.

And again, if I can help you with something else please cobtact me 👍🏼