tabularx support

[Zumiha]

Older versions (v0.9.10) supported {tabularx} package in \JSONParseArrayValuesMap
Newer versions introduced \JSONParseArrayMapFunction with backward compatibility for \JSONParseArrayValuesMap, but {tabularx} refuses to work with newer {jsonparse} versions.
Using \begin{tabular} instead of {tabularx} works fine with backward compatibility, but I really don't want to give up on those adjustable-width tables.
Did anyone had this issue?

[jasperhabicht]

Thank you for your enquiry. You did not provide a minimal working example, but the example from the manual indeed does not work with tabularx.

You are right, that current versions of jsonparse offer multiple ways to loop through arrays which are different from the functions that were available in older versions. Due to the different ways how tabular material or arrays or lists are parsed and typeset, I decided to extend the existing command \JSONParseArrayValuesMap and offer two variants of which one allows for mapping inline and the other allows for mapping using a function. Depending on how the package you use to typeset tabular material parses the code that represents the material to be typeset, you need to use the former or the latter (or another solution altogether).

The command \JSONParseArrayMapInline is pretty flexible and may be a solution for you:

\documentclass{article}
\usepackage{jsonparse}
\usepackage{tabularx}

\JSONParse{\myJSONdata}{
{
  "array" : [
    {
      "key_a" : "one" ,
      "key_b" : "two"
    } ,
    {
      "key_a" : "three" ,
      "key_b" : "four"
    }
  ]
}
}

\begin{document}

\begin{tabularx}{\textwidth}{ c X }
    \textbf{key a} &
    \textbf{key b} \\ \hline
    \JSONParseArrayMapInline{\myJSONdata}{array}{%
        \JSONParseValue{\myJSONdata}{array[#1].key_a} & 
        \JSONParseValue{\myJSONdata}{array[#1].key_b} \\
    }
    \hline
\end{tabularx}

\end{document}

But it really depends on your concrete use case whether this can be a working solution for you or not.

I need to investigate why there is this difference between tabular and tabularx environments.

[Zumiha]

Hello jasperhabicht! Thank you for clarification. I will try explaining in more detail.

In this issue I am using versions {jsonparse} {2024-12-10} {0.9.10} and {jsonparse} {2025-12-10} {1.6.10}
Old version using \JSONParseArrayValuesMap:

\documentclass{article}
\usepackage{jsonparse_0.9.10}
\usepackage{array}
\usepackage{tabularx}

\begin{document}

\JSONParse{\myJSON}
{
    {
        "array" : [
            {
                "key_a": "1 val a", 
                "key_b" : "1 val b"
            },
            {
                "key_a": "2 val a", 
                "key_b" : "2 val b"
            },
            {
                "key_a": "3 val a", 
                "key_b" : "3 val b"
            }
        ]
    }
}

\newcommand{\myJSONitem}
{
    \JSONParseArrayValueI & \JSONParseArrayValueII \\ \hline
}

tabular

\JSONParseArrayValuesMap{\myJSON}{array}[key_a,key_b]{myJSONitem}
    [\begin{tabular}{|m{50mm}|m{50mm}|}
        \hline
        \multicolumn{2}{|c|}{\textbf{array}}\\ \hline
        \textbf{key a} & \textbf{key b} \\ \hline]
    [\end{tabular}] 

\vspace{1em}
tabularx

\JSONParseArrayValuesMap{\myJSON}{array}[key_a,key_b]{myJSONitem}
    [\begin{tabularx}{100mm}{|m{50mm}|X|}
        \hline
        \multicolumn{2}{|c|}{\textbf{array}}\\ \hline
        \textbf{key a} & \textbf{key b} \\ \hline]
    [\end{tabularx}] 

\end{document}

When using {jsonparse} {2025-12-10} {1.6.10} tabularx part

\JSONParseArrayValuesMap{\myJSON}{array}[key_a,key_b]{myJSONitem}
    [\begin{tabularx}{100mm}{|m{50mm}|X|}
        \hline
        \multicolumn{2}{|c|}{\textbf{array}}\\ \hline
        \textbf{key a} & \textbf{key b} \\ \hline]
    [\end{tabularx}] 

will have fatal error and will not build.

Yes \JSONParseArrayMapInline works fine but there is issue with passing arguments.
If I using jsonparse in other package backward compatibility works with tabular:

\ProvidesPackage{jsontable}[json table]
\RequirePackage{jsonparse_1.6.10}
\RequirePackage{array}
\RequirePackage{tabularx}

\NewDocumentCommand{\drawinfotable}{m}
    \newcommand{\myJSONitem}
    {
        \JSONParseArrayValueI & \JSONParseArrayValueII \\ \hline
    }

    \JSONParseArrayValuesMap{#1}{array}[key_a,key_b]{myJSONitem}
        [\begin{tabular}{|m{50mm}|m{50mm}|}
            \hline
            \multicolumn{2}{|c|}{\textbf{array}}\\ \hline
            \textbf{key a} & \textbf{key b} \\ \hline]
        [\end{tabular}] 

but using workaround with \JSONParseArrayMapInline will not work correctly, my guess because we passing arguments as #1 to \JSONParseArray... and inline command also utilizing #1

    \begin{tabularx}{100mm}{|m{90mm}|X|}
        \textbf{key a} &
        \textbf{key b} \\ \hline
        \JSONParseArrayMapInline{#1}{array}{%
            \JSONParseValue{#1}{array[#1].key_a} & 
            \JSONParseValue{#1}{array[#1].key_b} \\
        }
        \hline
    \end{tabularx}

table renders and has correct number of rows but all cells display as empty.

[jasperhabicht]

The solution is to use the command \JSONParseArrayMapInline but you need to double the # which is something you always need to do if you want to nest functions to access the relevant argument (the following example assuming the current version of jsonparse):

\documentclass{article}
\usepackage{jsonparse,tabularx}

\NewDocumentCommand{\drawinfotable}{m}{
    \begin{tabularx}{100mm}{|m{90mm}|X|}
        \textbf{key a} &
        \textbf{key b} \\ \hline
        \JSONParseArrayMapInline{#1}{array}{%
            \JSONParseValue{#1}{array[##1].key_a} & 
            \JSONParseValue{#1}{array[##1].key_b} \\
        }
        \hline
    \end{tabularx}
}

\JSONParse{\myJSON}{
    {
        "array" : [
            {
                "key_a": "1 val a", 
                "key_b" : "1 val b"
            },
            {
                "key_a": "2 val a", 
                "key_b" : "2 val b"
            },
            {
                "key_a": "3 val a", 
                "key_b" : "3 val b"
            }
        ]
    }
}


\begin{document}

\drawinfotable{\myJSON}

\end{document}

As a rule of thumb, if you encounter issues with the command \JSONParseArrayMapFunction when trying to apply it to a tabular environment, try \JSONParseArrayMapInline or the other way around. In most cases, one of both should work.

You probably want to substitute \JSONParseFromFile by \JSONParse in your code example since you don't want to load a file but provide code as argument directly (substitute vice versa to make my code work with JSON code from a file).

[Zumiha]

Thank you jasperhabicht!
Yes this works. Will keep in mind about double #

P.s. Yes, in example there is typo. Of course it should be \JSONParse if using code as argument. I fixed example code in my answer.