more CG syntax. parsing the easy stuff

src/ast.ts

@@ -1,35 +1,24 @@
 import type { Value } from './types';
 
+
+// Literals and Variables
+
 export type Literal = {
     kind: 'literal'
     value: Value
 }
 
-export type BinaryOp = {
-    kind: 'binaryop'
-    operator: string
-    left: AST
-    right: AST
-}
-
 export type Variable = {
     kind: 'variable'
     name: string
 }
 
-export type Let = {
-    kind: 'let'
+export type Constructor = {
+    kind: 'constructor'
     name: string
-    value: AST
-    body: AST
 }
 
-export type If = {
-    kind: 'if'
-    condition: AST
-    then: AST
-    else: AST
-}
+// Functions
 
 export type Lambda = {
     kind: 'lambda'
@@ -43,4 +32,93 @@ export type Apply = {
     args: AST[]
 }
 
-export type AST = Literal | BinaryOp | Variable | Let | If | Lambda | Apply
+// Bindings
+
+export type Let = {
+    kind: 'let'
+    name: string
+    value: AST
+    body: AST
+}
+
+// Matching
+
+export type Match = {
+    kind: 'match'
+    expr: AST
+    cases: MatchCase[]
+}
+
+export type MatchCase = {
+    pattern: Pattern
+    result: AST
+}
+
+export type Pattern =
+    | { kind: 'wildcard' }
+    | { kind: 'var', name: string }
+    | { kind: 'literal', value: number | string }
+    | { kind: 'constructor', name: string, args: Pattern[] }
+    | { kind: 'list', elements: Pattern[] }
+    | { kind: 'record', fields: { [key: string]: Pattern } }
+
+// Data Structures
+
+export type Record = {
+    kind: 'record'
+    fields: { [key: string]: AST }
+}
+
+export type RecordAccess = {
+    kind: 'record-access'
+    record: AST
+    field: string
+}
+
+export type RecordUpdate = {
+    kind: 'record-update'
+    record: AST
+    updates: { [key: string]: AST }
+}
+
+export type List = {
+    kind: 'list'
+    elements: AST[]
+}
+
+// Top-level constructs
+
+export type Definition = {
+    kind: 'definition'
+    name: string
+    body: AST
+    // type?: string // TODO
+}
+
+export type TypeDef = {
+    kind: 'typedef'
+    name: string
+    variants: Array<{ name: string, args: string[] }>
+}
+
+export type Import = {
+    kind: 'import'
+    module: string
+    items: string[] | 'all'
+}
+
+export type AST =
+    | Literal
+    | Variable
+    | Constructor
+    | Lambda
+    | Apply
+    | Let
+    | Match
+    | Record
+    | RecordAccess
+    | RecordUpdate
+    | List
+    | Definition
+    | TypeDef
+    | Import