Soft dependencies

Typically you will define dependencies among your targets using the ==> and <== operators, and these dependencies define the order in which the targets are executed during a build.

You can also define soft dependencies among targets using the ?=> and <=? operators. For example, you might say that target B has a soft dependency on target A:

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"A" ?=> "B"
// Or equivalently
"B" <=? "A"

With this soft dependency, running B will not require that A be run first. However it does mean that if A is run (due to other dependencies) it must be run before B.

Example

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// *** Define Targets ***
Target "Clean" (fun () -> 
	trace " --- Cleaning stuff --- "
)

Target "Build" (fun () -> 
	trace " --- Building the app --- "
)

Target "Rebuild" DoNothing

// *** Define Dependencies ***
"Build" ==> "Rebuild"
"Clean" ==> "Rebuild"
// Make sure "Clean" happens before "Build", if "Clean" is executed during a build.
"Clean" ?=> "Build"

FAKE - F# Make

Soft dependencies

Example