feat(web): client support for transformation rules

6 files changed, 69 insertions, 19 deletions

diff --git a/language-web/src/main/js/editor/EditorParent.ts b/language-web/src/main/js/editor/EditorParent.ts
index b890ac3c..ee1323f6 100644
--- a/language-web/src/main/js/editor/EditorParent.ts
+++ b/language-web/src/main/js/editor/EditorParent.ts
@@ -127,7 +127,7 @@ export const EditorParent = styled('div')(({ theme }) => {
     '.cmt-keyword': {
       color: theme.palette.primary.main,
     },
-    '.cmt-typeName, .cmt-atom': {
+    '.cmt-typeName, .cmt-macroName, .cmt-atom': {
       color: theme.palette.text.primary,
     },
     '.cmt-variableName': {
diff --git a/language-web/src/main/js/index.tsx b/language-web/src/main/js/index.tsx
index 595498fc..dfecde37 100644
--- a/language-web/src/main/js/index.tsx
+++ b/language-web/src/main/js/index.tsx
@@ -31,6 +31,13 @@ pred invalidTaxStatus(Person p) <->
     parent(p, q),
     !taxStatus(q, retired).
 
+direct rule createChild(p):
+    children(p, newPerson) = unknown,
+    equals(newPerson, newPerson) = unknown
+ ~> new q,
+    children(p, q) = true,
+    taxStatus(q, child) = true.
+
 unique family.
 Family(family).
 members(family, anne).
diff --git a/language-web/src/main/js/language/folding.ts b/language-web/src/main/js/language/folding.ts
index 54c7294d..5d51f796 100644
--- a/language-web/src/main/js/language/folding.ts
+++ b/language-web/src/main/js/language/folding.ts
@@ -75,18 +75,22 @@ export function foldDeclaration(node: SyntaxNode, state: EditorState): FoldRange
  * @param node the node to fold
  * @returns the folding range or `null` is there is nothing to fold
  */
-export function foldConjunction(node: SyntaxNode): FoldRange | null {
+function foldWithSibling(node: SyntaxNode): FoldRange | null {
   const { parent } = node;
   if (parent === null) {
     return null;
   }
-  const { cursor } = parent;
-  let nConjunctions = 0;
-  while (cursor.next()) {
+  const { firstChild } = parent;
+  if (firstChild === null) {
+    return null;
+  }
+  const { cursor } = firstChild;
+  let nSiblings = 0;
+  while (cursor.nextSibling()) {
     if (cursor.type === node.type) {
-      nConjunctions += 1;
+      nSiblings += 1;
     }
-    if (nConjunctions >= 2) {
+    if (nSiblings >= 2) {
       return {
         from: node.from,
         to: node.to,
@@ -95,3 +99,17 @@ export function foldConjunction(node: SyntaxNode): FoldRange | null {
   }
   return null;
 }
+
+export function foldWholeNode(node: SyntaxNode): FoldRange {
+  return {
+    from: node.from,
+    to: node.to,
+  };
+}
+
+export function foldConjunction(node: SyntaxNode): FoldRange | null {
+  if (node.parent?.type?.name === 'PredicateBody') {
+    return foldWithSibling(node);
+  }
+  return foldWholeNode(node);
+}
diff --git a/language-web/src/main/js/language/indentation.ts b/language-web/src/main/js/language/indentation.ts
index 973b4a80..78f0a750 100644
--- a/language-web/src/main/js/language/indentation.ts
+++ b/language-web/src/main/js/language/indentation.ts
@@ -75,10 +75,13 @@ export function indentDeclaration(context: TreeIndentContext): number {
   return indentDeclarationStrategy(context, 1);
 }
 
-export function indentPredicate(context: TreeIndentContext): number {
+export function indentPredicateOrRule(context: TreeIndentContext): number {
   const clauseIndent = indentDeclarationStrategy(context, 1);
   if (/^\s+(;|\.)/.exec(context.textAfter) !== null) {
     return clauseIndent - 2;
   }
+  if (/^\s+(~>)/.exec(context.textAfter) !== null) {
+    return clauseIndent - 3;
+  }
   return clauseIndent;
 }
diff --git a/language-web/src/main/js/language/problem.grammar b/language-web/src/main/js/language/problem.grammar
index cf940698..c242a4ba 100644
--- a/language-web/src/main/js/language/problem.grammar
+++ b/language-web/src/main/js/language/problem.grammar
@@ -14,9 +14,15 @@ statement {
     (EnumBody { "{" sep<",", UniqueNodeName> "}" } | ".")
   } |
   PredicateDefinition {
-    (ckw<"error"> ckw<"pred">? | ckw<"pred">) RelationName ParameterList<Parameter>?
+    (ckw<"error"> ckw<"pred">? | ckw<"direct">? ckw<"pred">)
+    RelationName ParameterList<Parameter>?
     PredicateBody { ("<->" sep<OrOp, Conjunction>)?  "." }
   } |
+  RuleDefinition {
+    ckw<"direct">? ckw<"rule">
+    RuleName ParameterList<Parameter>?
+    RuleBody { ":" sep<OrOp, Conjunction> "~>" sep<OrOp, Action> "." }
+  } |
   Assertion {
     ckw<"default">? (NotOp | UnknownOp)? RelationName
     ParameterList<AssertionArgument> (":" LogicValue)? "."
@@ -47,9 +53,17 @@ Conjunction { ("," | Literal)+ }
 
 OrOp { ";" }
 
-Literal { NotOp? Atom }
+Literal { NotOp? Atom (("=" | ":") sep1<"|", LogicValue>)? }
+
+Atom { RelationName "+"? ParameterList<Argument> }
 
-Atom { RelationName ParameterList<Argument>? }
+Action { ("," | ActionLiteral)+ }
+
+ActionLiteral {
+   ckw<"new"> VariableName |
+   ckw<"delete"> VariableName |
+   Literal
+}
 
 Argument { VariableName | Constant }
 
@@ -67,6 +81,8 @@ Multiplicity { (IntMult "..")? (IntMult | StarMult)}
 
 RelationName { QualifiedName }
 
+RuleName { QualifiedName }
+
 UniqueNodeName { QualifiedName }
 
 VariableName { QualifiedName }
@@ -83,7 +99,7 @@ ParameterList<content> { "(" sep<",", content> ")" }
 
 sep<separator, content> { sep1<separator, content>? }
 
-sep1<separator, content> { content (separator content?)* }
+sep1<separator, content> { content (separator content)* }
 
 @skip { LineComment | BlockComment | whitespace }
 
@@ -123,7 +139,7 @@ sep1<separator, content> { content (separator content?)* }
 
   StarArgument { "*" }
 
-  "{" "}" "(" ")" "[" "]" "." ".." "," ":" "<->"
+  "{" "}" "(" ")" "[" "]" "." ".." "," ":" "<->" "~>"
 }
 
 @detectDelim
diff --git a/language-web/src/main/js/language/problemLanguageSupport.ts b/language-web/src/main/js/language/problemLanguageSupport.ts
index 80d25d71..ab1c55f9 100644
--- a/language-web/src/main/js/language/problemLanguageSupport.ts
+++ b/language-web/src/main/js/language/problemLanguageSupport.ts
@@ -14,11 +14,12 @@ import {
   foldBlockComment,
   foldConjunction,
   foldDeclaration,
+  foldWholeNode,
 } from './folding';
 import {
   indentBlockComment,
   indentDeclaration,
-  indentPredicate,
+  indentPredicateOrRule,
 } from './indentation';
 
 const parserWithMetadata = (parser as LRParser).configure({
@@ -26,9 +27,10 @@ const parserWithMetadata = (parser as LRParser).configure({
     styleTags({
       LineComment: t.lineComment,
       BlockComment: t.blockComment,
-      'problem class enum pred unique scope': t.definitionKeyword,
-      'abstract extends refers contains opposite error default': t.modifier,
+      'problem class enum pred rule unique scope': t.definitionKeyword,
+      'abstract extends refers contains opposite error direct default': t.modifier,
       'true false unknown error': t.keyword,
+      'new delete': t.operatorKeyword,
       NotOp: t.keyword,
       UnknownOp: t.keyword,
       OrOp: t.keyword,
@@ -37,19 +39,21 @@ const parserWithMetadata = (parser as LRParser).configure({
       StarMult: t.number,
       String: t.string,
       'RelationName/QualifiedName': t.typeName,
+      'RuleName/QualifiedName': t.macroName,
       'UniqueNodeName/QualifiedName': t.atom,
       'VariableName/QualifiedName': t.variableName,
       '{ }': t.brace,
       '( )': t.paren,
       '[ ]': t.squareBracket,
       '. .. , :': t.separator,
-      '<->': t.definitionOperator,
+      '<-> ~>': t.definitionOperator,
     }),
     indentNodeProp.add({
       ProblemDeclaration: indentDeclaration,
       UniqueDeclaration: indentDeclaration,
       ScopeDeclaration: indentDeclaration,
-      PredicateBody: indentPredicate,
+      PredicateBody: indentPredicateOrRule,
+      RuleBody: indentPredicateOrRule,
       BlockComment: indentBlockComment,
     }),
     foldNodeProp.add({
@@ -57,7 +61,9 @@ const parserWithMetadata = (parser as LRParser).configure({
       EnumBody: foldInside,
       ParameterList: foldInside,
       PredicateBody: foldInside,
+      RuleBody: foldInside,
       Conjunction: foldConjunction,
+      Action: foldWholeNode,
       UniqueDeclaration: foldDeclaration,
       ScopeDeclaration: foldDeclaration,
       BlockComment: foldBlockComment,
@@ -75,7 +81,7 @@ const problemLanguage = LRLanguage.define({
       },
       line: '%',
     },
-    indentOnInput: /^\s*(?:\{|\}|\(|\)|;|\.)$/,
+    indentOnInput: /^\s*(?:\{|\}|\(|\)|;|\.|~>)$/,
   },
 });