Remove unnecessary use of eval from install script
#226
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The "template" installation script hosted in this repository contains a `checkLatestVersion()` function which is used to determine the latest version of the project when the user does not specify a version to install. The version number is required by the caller, but shell functions do not support returning such content. As a workaround, the script author set up a system where the caller passed an arbitrary variable name to the function. The function then sets a global variable of that name with the release name. So it resembles a "pass by reference" approach, but isn't. This was done using the `eval` builtin. This tool must be used with caution and best practices is to avoid it unless absolutely necessary. The system used by the script has some value for a reusable function. However, in this case the function is only intended for internal use by the script, and is called only once. So the unintuitive nature of this system and potential for bugs don't bring any benefits when compared with the much more straightforward approach of simply using a fixed name for the global variable used to store the release name.
per1234
added
type: enhancement
umbynos
approved these changes
Apr 21, 2022
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The "template" installation script hosted in this repository contains a
checkLatestVersion()function which is used to determine the latest version of the project when the user does not specify a version to install.The version number is required by the caller, but shell functions do not support returning such content.
As a workaround, the script author set up a system where the caller passed an arbitrary variable name to the function. The function then sets a global variable of that name with the release name. So it resembles a "pass by reference" approach, but isn't.
This was done using the
evalbuiltin. This tool must be used with caution and best practices is to avoid it unless absolutely necessary. The system used by the script has some value for a reusable function. However, in this case the function is only intended for internal use by the script, and is called only once. So the unintuitive nature of this system and potential for bugs (e.g., arduino/arduino-cli#1714) don't bring any benefits when compared with the much more straightforward approach of simply using a fixed name for the global variable used to store the release name.Related: #222