diff options
| -rw-r--r-- | changelog.md | 31 | ||||
| -rw-r--r-- | compiler/semstmts.nim | 18 | ||||
| -rw-r--r-- | doc/manual.rst | 1 | ||||
| -rw-r--r-- | tests/pragmas/ttypedef_macro.nim | 66 |
4 files changed, 110 insertions, 6 deletions
diff --git a/changelog.md b/changelog.md index 1636d125f..8e70513e0 100644 --- a/changelog.md +++ b/changelog.md @@ -13,7 +13,36 @@ ## Language changes - +- Pragma macros on type definitions can now return `nnkTypeSection` nodes as well as `nnkTypeDef`, + allowing multiple type definitions to be injected in place of the original type definition. + + ```nim + import macros + + macro multiply(amount: static int, s: untyped): untyped = + let name = $s[0].basename + result = newNimNode(nnkTypeSection) + for i in 1 .. amount: + result.add(newTree(nnkTypeDef, ident(name & $i), s[1], s[2])) + + type + Foo = object + Bar {.multiply: 3.} = object + x, y, z: int + Baz = object + + # becomes + + type + Foo = object + Bar1 = object + x, y, z: int + Bar2 = object + x, y, z: int + Bar3 = object + x, y, z: int + Baz = object + ``` ## Compiler changes diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim index 4607e857a..36d76608e 100644 --- a/compiler/semstmts.nim +++ b/compiler/semstmts.nim @@ -1112,7 +1112,12 @@ proc typeDefLeftSidePass(c: PContext, typeSection: PNode, i: int) = if name.kind == nkPragmaExpr: let rewritten = applyTypeSectionPragmas(c, name[1], typeDef) if rewritten != nil: - typeSection[i] = rewritten + case rewritten.kind + of nkTypeDef: + typeSection[i] = rewritten + of nkTypeSection: + typeSection.sons[i .. i] = rewritten.sons + else: illFormedAst(rewritten, c.config) typeDefLeftSidePass(c, typeSection, i) return pragma(c, s, name[1], typePragmas) @@ -1143,16 +1148,19 @@ proc typeDefLeftSidePass(c: PContext, typeSection: PNode, i: int) = proc typeSectionLeftSidePass(c: PContext, n: PNode) = # process the symbols on the left side for the whole type section, before # we even look at the type definitions on the right - for i in 0..<n.len: + var i = 0 + while i < n.len: # n may grow due to type pragma macros var a = n[i] when defined(nimsuggest): if c.config.cmd == cmdIdeTools: inc c.inTypeContext suggestStmt(c, a) dec c.inTypeContext - if a.kind == nkCommentStmt: continue - if a.kind != nkTypeDef: illFormedAst(a, c.config) - typeDefLeftSidePass(c, n, i) + case a.kind + of nkCommentStmt: discard + of nkTypeDef: typeDefLeftSidePass(c, n, i) + else: illFormedAst(a, c.config) + inc i proc checkCovariantParamsUsages(c: PContext; genericType: PType) = var body = genericType[^1] diff --git a/doc/manual.rst b/doc/manual.rst index 328035b6d..a4701c85b 100644 --- a/doc/manual.rst +++ b/doc/manual.rst @@ -7755,6 +7755,7 @@ This is translated to: This is translated to a call to the `schema` macro with a `nnkTypeDef` AST node capturing both the left-hand side and right-hand side of the definition. The macro can return a potentially modified `nnkTypeDef` tree +or multiple `nnkTypeDef` trees contained in a `nnkTypeSection` node which will replace the original row in the type section. When multiple macro pragmas are applied to the same definition, the diff --git a/tests/pragmas/ttypedef_macro.nim b/tests/pragmas/ttypedef_macro.nim new file mode 100644 index 000000000..dd4c87757 --- /dev/null +++ b/tests/pragmas/ttypedef_macro.nim @@ -0,0 +1,66 @@ +import macros + +macro makeref(s): untyped = + expectKind s, nnkTypeDef + result = newTree(nnkTypeDef, s[0], s[1], newTree(nnkRefTy, s[2])) + +type + Obj {.makeref.} = object + a: int + +doAssert Obj is ref +doAssert Obj(a: 3)[].a == 3 + +macro multiply(amount: static int, s): untyped = + let name = $s[0].basename + result = newNimNode(nnkTypeSection) + for i in 1 .. amount: + result.add(newTree(nnkTypeDef, ident(name & $i), s[1], s[2])) + +type + Foo = object + Bar {.multiply: 2.} = object + x, y, z: int + Baz = object + +let bar1 = Bar1(x: 1, y: 2, z: 3) +let bar2 = Bar2(x: bar1.x, y: bar1.y, z: bar1.z) +doAssert Bar1 isnot Bar2 +doAssert not declared(Bar) +doAssert not declared(Bar3) + +# https://github.com/nim-lang/RFCs/issues/219 + +macro inferKind(td): untyped = + let name = $td[0].basename + var rhs = td[2] + while rhs.kind in {nnkPtrTy, nnkRefTy}: rhs = rhs[0] + if rhs.kind != nnkObjectTy: + result = td + else: + for n in rhs[^1]: + if n.kind == nnkRecCase and n[0][^2].eqIdent"_": + let kindTypeName = ident(name & "Kind") + let en = newTree(nnkEnumTy, newEmptyNode()) + for i in 1 ..< n.len: + let branch = n[i] + if branch.kind == nnkOfBranch: + for j in 0 ..< branch.len - 1: + en.add(branch[j]) + n[0][^2] = kindTypeName + return newTree(nnkTypeSection, + newTree(nnkTypeDef, kindTypeName, newEmptyNode(), en), + td) + +type Node {.inferKind.} = ref object + case kind: _ + of opValue: value: int + of opAdd, opSub, opMul, opCall: kids: seq[Node] + +doAssert opValue is NodeKind +let node = Node(kind: opMul, kids: @[ + Node(kind: opValue, value: 3), + Node(kind: opValue, value: 5) +]) +doAssert node.kind == opMul +doAssert node.kids[0].value * node.kids[1].value == 15 |