75 lines
1.7 KiB
Plaintext
75 lines
1.7 KiB
Plaintext
module Spoofax-Propositional-Language
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/** md:
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Title: Concrete Syntax
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## Concrete Syntax
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The current Spoofax/Eclipse IDE is oriented around individual language
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projects. Therefore in order to work with ASTs of the SPL
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[abstract syntax](../README.md#abstract-syntax) that we just saw, it's easiest to
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define a concrete syntax for SPL, via the following SDF3 definition:
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*[SPL]: Spoofax Propositional Language
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```sdf3
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**/
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imports
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Common
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context-free sorts
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Prop String
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context-free start-symbols
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Prop
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/** md (include the following code in the documentation) */
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context-free syntax
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Prop.True = <1>
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Prop.False = <0>
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Prop.Atom = String
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Prop.Not = <!<Prop>>
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Prop.And = <<Prop> & <Prop>>
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Prop.Or = <<Prop> | <Prop>>
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Prop.Impl = [[Prop] -> [Prop]]
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Prop.Eq = <<Prop> = <Prop>>
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Prop = <(<Prop>)> {bracket}
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String = ID
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context-free priorities
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Prop.Not
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> Prop.And
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> Prop.Or
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> Prop.Impl
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> Prop.Eq
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/* [stop to avoid the open-comment in the extracted markdown] **/
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/** md [conclusion of the documentation]
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```
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Thus, the first two example AST expressions
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`A: {! examples/sec4.1_A.aterm !}` and
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`B: {! examples/sec4.1_B.aterm !}`
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from {! ../docrefs/sec4.1.md !} can be generated by the following much more
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compact SPL expressions:
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`A: {! examples/sec4.1_A.spl !}` and
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`B: {! examples/sec4.1_B.spl !}`. (If you are following along in the repository,
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you can visit the file `syntax/examples/sec4.1_A.spl` (or ...`_B.spl`) and from the
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Spoofax menu select "Syntax > Show parsed AST" to see the AST generation
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in action.)
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This concrete syntax actually makes it easier to construct the example
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expressions used throughout the tutorial manual as examples for Stratego
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processing.
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**/
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