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If you want the script to exit even when it hits an error, you can use an [http://www.jsoftware.com/help/dictionary/dx009.htm#26 immex phrase], which will be the first thing executed by the event loop, before it prompts. |
If you want the script to exit even when it hits an error, you can use an [http://www.jsoftware.com/help/dictionary/dx009.htm#26 immex phrase], which will be the first thing executed by the event loop, before it prompts. |
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=={{header|jq}}== |
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A jq program consists of a (possibly empty) sequence of directives and function definitions followed by a single (but possibly compound) jq expression that is evaluated in the context of the prior definitions. The jq expression can take many forms, such as a single JSON value, or a pipeline of filters. In particular, it could be the invocation of a previously defined function named main as in this example: |
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<syntaxhighlight lang="jq"> |
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def main: |
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"Hello, World!"; |
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main |
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</syntaxhighlight> |
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The jq interpreter has two modes of operation: a data-driven mode (the default) and an autonomous mode (corresponding to the `-n` command-line option). |
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In general, in the data-driven mode, the expression at the end of the jq program is evaluated once for each input, so that in the above example, |
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the "Hello, World!" string would be emitted once for each input. |
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By contrast, if the `-n` command-line option is specified, then a single JSON `null` would be presented to the final expression, so that in the above example, |
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the string wold be emitted just once. |
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=={{header|Julia}}== |
=={{header|Julia}}== |
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