83 lines
2.9 KiB
Plaintext
83 lines
2.9 KiB
Plaintext
/** md
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Title: Running a Strategy
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## Running a Strategy
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The first example of running a Stratego strategy
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in the {! ../docrefs/manual.md !} is that of _evaluating_ an AST,
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via the `prop-eval-rules` module in {! ../docrefs/sec4.1.md !}. In this
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repository, we've placed those rules in `trans/prop-eval-rules.str`,
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and the glue strategies that call them in `trans/prop-eval.str`. This latter
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module is imported by `trans/spoofax_propositional_language.str`.
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(I am unclear on what triggers Editor Services to use this particular Stratego
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file, but in any automatically-generated Spoofax project there will be a
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main language Stratego file in the `trans` directory, and that's the file
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from which the rule specified in an ESV `action` has to be visible.)
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There's an Editor Services module `editor/Manual.esv` to invoke the eval strategy,
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and it's included in in `editor/Main.esv.`
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With all of these elements in place, you should now be able to invoke
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the `eval` rule from the "Spoofax" menu. For example, to execute the "test1"
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example from the Spoofax Tutorial/Reference
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{! ../docrefs/sec4.1.md !}, navigate to the
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file `syntax/examples/sec4.1_test1.spl`:
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```SPL
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{! ../syntax/examples/sec4.1_test1.spl !}
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```
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and select "Spoofax > Manual > prop-eval" from the menu bar to produce:
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```
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{! ../syntax/examples/sec4.1_test1.eval.aterm !}
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```
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You can do the same with test2:
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```SPL
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{! ../syntax/examples/sec4.1_test2.spl !}
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```
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to produce
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```
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{! ../syntax/examples/sec4.1_test2.eval.aterm !}
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```
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Both of these results match the expected output of the `eval` transformation
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as shown in {! ../docrefs/sec4.1.md !}.
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One other note about the files provided in this repository. The "do-XXX" rule
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used as boilerplate glue between ESV and a Stratego strategy in
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`trans/prop-eval.str` is:
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```Stratego
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{! prop-eval.str extract: {start: '^(.*Interface.*\s*)$'} !}
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```
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The version of this glue being used here corresponds to what's used in the example
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[Calc language project](https://github.com/MetaBorgCube/metaborg-calc),
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but is slightly different from what is described in the
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[Menus section](http://www.metaborg.org/en/latest/source/langdev/meta/lang/esv.html#menus)
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of the ESV Manual. I am unclear on the significance of this difference or which
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form is "better" -- I simply modeled this Stratego code after the code in the
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working Calc repository, and all seems to be well.
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**/
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module prop-eval-rules
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imports signatures/-
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rules
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E : Not(True()) -> False()
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E : Not(False()) -> True()
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E : And(True(), x) -> x
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E : And(x, True()) -> x
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E : And(False(), x) -> False()
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E : And(x, False()) -> False()
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E : Or(True(), x) -> True()
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E : Or(x, True()) -> True()
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E : Or(False(), x) -> x
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E : Or(x, False()) -> x
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E : Impl(True(), x) -> x
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E : Impl(x, True()) -> True()
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E : Impl(False(), x) -> True()
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E : Impl(x, False()) -> Not(x)
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E : Eq(False(), x) -> Not(x)
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E : Eq(x, False()) -> Not(x)
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E : Eq(True(), x) -> x
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E : Eq(x, True()) -> x
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