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ayush_vipul's avatar
ayush_vipul
New Contributor III
7 years ago
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Accessing one expression library functions from another expression lib

Hi I have a use case where I am looking forward to access methods of one library(expression file) from another library (expression file 2). Is their a way to achieve this?
  • tstack's avatar
    tstack
    7 years ago

    Since the CSV Formatter currently doesn’t work with arrays, you will need to use a child pipeline that splits the array into separate docs that go into a CSV Formatter.

    I’m attaching a couple of pipelines to demonstrate this flow:

    FormatArrayToCSV_2019_02_28.slp (5.6 KB)
    WriteCSVFiles_2019_02_28.slp (5.4 KB)

    The FormatArrayToCSV pipeline is the child. It splits the “$array” property in the incoming document and then passes the results to a CSV Formatter and FileWriter. You’ll need to change the JSON Splitter to split your array property.

    The WriteCSVFiles pipeline is the parent. It just contains some mock data and feeds it into the child pipeline.

tstack's avatar
tstack
Former Employee
7 years ago
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Do you mean without the lib.libname prefix? No, libraries are always imported under the lib object.

I’m not sure what you mean by this, can you give an example?

ayush_vipul's avatar
ayush_vipul
New Contributor III
7 years ago
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Hi @tstack by global scope in my query. I meat I have a expression file where we can decalre a function on top level which could be accessed from anywhere in the object(same expression file) using something like globalthis Or this (basically " this context" which would resolve at any herarical level throughout the file)

  • tstack's avatar
    tstack
    Former Employee
    7 years ago
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    I think I understand now… Take a look at the Object Literal documentation where it mentions some of the variables that you can use to reference other parts of a nested literal. I think probably want to use __root__ for your situation.

    Maybe something like the following (I haven’t tried it out):

    {
    value: 42,
    child: {
        adder: x => __root__.value + x
    }
}
    • ayush_vipul's avatar
      ayush_vipul
      New Contributor III
      7 years ago
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      thanks @tstack .This was the exact use case.

      Also do we have a total number of libraries we can add to a pipeline ?
      Do we have a standerd IDE to write expressions ?
      or if you can suggest any extension for VS code.

      • tstack's avatar
        tstack
        Former Employee
        7 years ago
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        I don’t think so.

        The expression language is mostly a subset of JavaScript, so I would just use an editor with support for that. The main difference is that expression language is just expressions, not statements. Don’t try to use things like if or function(), you need to stick to arrow functions (e.g. (x, y) => x + y). One addition to the e-lang that is not in JavaScript is the match operator. You might find that useful if you have to do a lot of conditionals.