WIP

src/expression.pegjs

@@ -1,4 +1,6 @@
 {
+	/* FIXME: `or` operator */
+
 	let operators = [{
 		associativity: "left",
 		operators: ["call"]
@@ -101,7 +103,7 @@ escapableCharacter
 	/ "t"
 	/ "r"
 
-commentCharacter
+inlineCommentCharacter
 	= [^\n\r]
 
 // Literals
@@ -129,14 +131,20 @@ homePath
 storePath
 	= "<" path:([a-zA-Z0-9\.\_\-\+]+ ("/" [a-zA-Z0-9\.\_\-\+]+)*) ">" { return {type: "path", pathType: "store", storePath: path}; }
 
+uri
+	= [a-zA-Z][a-zA-Z0-9+\-.]* ":" [a-zA-Z0-9%/?:@&=+$,\-_.!~*']+
+
 // Utilities
 _
-	= (whitespace / comment)* {}
+	= (whitespace / inlineComment)* {}
 
 __
 	= whitespace+ {}
 
-reservedWord // FIXME: Missing reserved words?
+reservedWord
+	= name:reservedWordName (& [^a-zA-Z0-9._-]) { return name; } // FIXME: Unify identifier character set definition
+
+reservedWordName // FIXME: Missing reserved words?
 	= "if"
 	/ "then"
 	/ "else"
@@ -171,11 +179,13 @@ nonOperatorExpression
 	/ withStatement
 	/ conditional
 	/ path
-	/ identifier
+	/ uri
+	/ attributePathAlternate
 
-comment
-	= "#" chars:commentCharacter* _ { return {type: "comment", text: chars.join("")} }
+inlineComment
+	= "#" chars:inlineCommentCharacter* _ { return {type: "inlineComment", text: chars.join("")} }
 
+/* FIXME: Where else to allow blockComments? Needs to be allowed everywhere, not just in expressions. */
 blockComment
 	= "/*" segments:(! "*/" . [^*]*)* "*/" { return {type: "blockComment", text: joinBlockText(segments)} }
 
@@ -187,7 +197,7 @@ functionCallOperatorExpression
 hasAttributeOperatorExpression
 	= left:nonOperatorExpression
 	_ "?"
-	_ right:identifier { return {type: "operatorExpression", operator: "?", left: left, right: right} } // FIXME: attribute path
+	_ right:identifier { return {type: "operatorExpression", operator: "?", left: left, right: right} } /* FIXME: Is an attribute path allowed here? */
 
 binaryOperatorExpression
 	= left:nonOperatorExpression
@@ -197,22 +207,49 @@ binaryOperatorExpression
 divisionOperatorExpression
 	= left:nonOperatorExpression
 	_ "/"
-	_ right:expression { return {type: "operatorExpression", operator: "/", left: left, right: right} }
+	_ right:expression {
+		return {type: "operatorExpression", operator: "/", left: left, right: right};
+	}
 
 numericallyNegatedOperatorExpression
 	= "-"
-	_ right:expression { return {type: "operatorExpression", operator: "numericalNegate", right: right} }
+	_ right:expression {
+		return {type: "operatorExpression", operator: "numericalNegate", right: right};
+	}
 
 booleanNegatedOperatorExpression
 	= "!"
-	_ right:expression { return {type: "operatorExpression", operator: "booleanNegate", right: right} }
+	_ right:expression {
+		return {type: "operatorExpression", operator: "booleanNegate", right: right};
+	}
+
+attributePathAlternate
+	= attributePath:attributePath alternate:(_ "or" _ attributePathAlternate)? {
+		if (alternate != null) {
+			return {type: "attributePathAlternate", path: attributePath, alternate: alternate};
+		} else {
+			return attributePath;
+		}
+	}
+
+attributePath
+	= firstIdentifier:attributeItem nextIdentifiers:("." attributeItem)* {
+		return {type: "attributePath", items: [firstIdentifier].concat(nextIdentifiers.map(item => item[1]))};
+	}
+
+attributeItem
+	= "\"" identifier:identifier "\"" { return identifier; } /* FIXME: What characters should be allowed here? */
+	/ identifier:identifier { return identifier; }
 
 identifier
-	= identifier:(! (reservedWord [^a-z0-9._-]) identifierValue) { return {type: "identifier", identifier: identifier[1]} }
+	= identifier:(! reservedWord identifierValue) {
+		return {type: "identifier", identifier: identifier[1]};
+	}
 
+/* FIXME: Quoted attributes? */
 identifierValue
 	= literal:stringLiteral { return literal.value; }
-	/ chars:[a-z_]i [a-z0-9._-]i+ { return text(); }
+	/ chars:[a-z_]i [a-z0-9_-]i+ { return text(); }
 
 group
 	= "("
@@ -233,17 +270,18 @@ functionDefinitionArgument
 	= identifier
 	/ setPattern
 
+/* FIXME: Is `"foo" = "bar"` valid in an assignment list? */
 assignment
-	= identifier:identifier
+	= attributePath:attributePath
 	_ "="
 	_ expression:reorderedExpression
-	_ ";" { return {type: "assignment", identifier: identifier, expression: expression} }
+	_ ";" { return {type: "assignment", attributePath: attributePath, expression: expression} }
 
 assignmentList
-	= _ items:((assignment / inheritStatement) _)* { return items.map(item => item[0]); }
+	= _ items:((assignment / inheritStatement / blockComment) _)* { return items.map(item => item[0]); }
 
-bindingList
-	= items:(assignment _)* { return {type: "bindings", assignments: items.map(item => item[0])} }
+bindingList // FIXME: Allow inherit - point at assignmentList instead?
+	= items:((assignment / blockComment) _)* { return {type: "bindings", assignments: items.map(item => item[0])} }
 
 set
 	= "{"
@@ -279,18 +317,20 @@ elseClause
 	= "else"
 	_ alternative:expression { return alternative; }
 
+/* FIXME: What to return here? */
 withStatement
 	= "with"
-	_ identifier:identifier
+	_ withExpression:expression
 	_ ";"
 	_ expression
 
-inheritStatement // FIXME: Distinguish between identifiers and attribute paths?
+inheritStatement /* FIXME: Distinguish between identifiers and attribute paths? */
 	= "inherit"
-	_ namespace:("(" identifier ")")?
-	_ identifiers:(identifier _)+
-	_ ";" { return {type: "inheritStatement", identifiers: identifiers.map(item => item[0]), namespace: maybe(namespace, 1)} }
+	_ namespace:("(" reorderedExpression ")")?
+	_ attributePaths:(attributePathAlternate _)+ /* FIXME: Is attributePathAlternate allowed here, or just attributePath? */
+	_ ";" { return {type: "inheritStatement", attributePaths: attributePaths.map(item => item[0]), namespace: maybe(namespace, 1)} }
 
+/* FIXME: Are attribute paths allowed in set patterns? */
 setPattern
 	= "{"
 	_ args:setPatternVariableList

test/fail-list-if.nix

@@ -0,0 +1 @@
+[if a then b else c]

test/fail-plus-if.nix

@@ -0,0 +1 @@
+1 + if true then 1 else 2

test/let-inherit.nix

@@ -0,0 +1 @@
+let inherit bar; in {}

test/with-if.nix

@@ -0,0 +1 @@
+with if false then {} else {x = 2;}; x