Jexl toLowerCase() and replace()

Question

I am using jexl.eval function to evaluate a value as follows-

jexl.eval("dataset[0].data['Entity Name'].toLowerCase().replace(/ /g, '_')",data);

dataset[0].data['Entity Name'] is always a string and is never null, there seems to be some error in jexl.eval, It returns empty string always

I wanted to confirm if toLowerCase() and replace() are supported or not? whether there is some issue in my syntax?

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Answer 1

toLowerCase() and replace are supported methods for string manipulation but you're using the wrong syntax which may be one of the reasons for unwanted output.

In JEXL, you can use the | (pipe) operator to chain transformations on a value. So, to properly use them, you need to define thee transform functions(for toLowerCase and replace) before using them in your JEXL expression. Something like:

jexl.eval("dataset[0].data['Entity Name'] | lower | replace(' ', '_')", data);

// Tranformations 
jexl.addTransform('lower', (val) => val.toLowerCase());
jexl.addTransform('replace', (val, search, replacement) => val.replace(new RegExp(search, 'g'), replacement));

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