all: nested sum types (#6913)

pull/6926/head
Daniel Däschle 2020-11-23 16:16:13 +01:00 committed by GitHub
parent c7ca1e7e13
commit 96539e43b5
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
8 changed files with 146 additions and 58 deletions

View File

@ -365,7 +365,7 @@ pub:
is_arg bool // fn args should not be autofreed
pub mut:
typ table.Type
sum_type_cast table.Type
sum_type_casts []table.Type // nested sum types require nested smart casting, for that a list of types is needed
pos token.Position
is_used bool
is_changed bool // to detect mutable vars that are never changed
@ -379,7 +379,7 @@ pub:
name string
pos token.Position
typ table.Type
sum_type_cast table.Type
sum_type_casts []table.Type // nested sum types require nested smart casting, for that a list of types is needed
}
pub struct GlobalField {

View File

@ -1801,7 +1801,7 @@ pub fn (mut c Checker) selector_expr(mut selector_expr ast.SelectorExpr) table.T
if !prevent_sum_type_unwrapping_once {
scope := c.file.scope.innermost(selector_expr.pos.pos)
if scope_field := scope.find_struct_field(utyp, field_name) {
return scope_field.sum_type_cast
return scope_field.sum_type_casts.last()
}
}
}
@ -3234,9 +3234,9 @@ pub fn (mut c Checker) ident(mut ident ast.Ident) table.Type {
c.error('undefined variable `$ident.name` (used before declaration)',
ident.pos)
}
is_sum_type_cast := obj.sum_type_cast != 0 && !c.prevent_sum_type_unwrapping_once
is_sum_type_cast := obj.sum_type_casts.len != 0 && !c.prevent_sum_type_unwrapping_once
c.prevent_sum_type_unwrapping_once = false
mut typ := if is_sum_type_cast { obj.sum_type_cast } else { obj.typ }
mut typ := if is_sum_type_cast { obj.sum_type_casts.last() } else { obj.typ }
if typ == 0 {
if mut obj.expr is ast.Ident {
if obj.expr.kind == .unresolved {
@ -3561,37 +3561,47 @@ fn (mut c Checker) match_exprs(mut node ast.MatchExpr, type_sym table.TypeSymbol
mut scope := c.file.scope.innermost(branch.pos.pos)
match mut node.cond {
ast.SelectorExpr {
mut is_mut := false
mut sum_type_casts := []table.Type{}
expr_sym := c.table.get_type_symbol(node.cond.expr_type)
field := c.table.struct_find_field(expr_sym, node.cond.field_name) or {
table.Field{}
if field := c.table.struct_find_field(expr_sym, node.cond.field_name) {
is_mut = field.is_mut
}
if field := scope.find_struct_field(node.cond.expr_type, node.cond.field_name) {
sum_type_casts << field.sum_type_casts
}
is_mut := field.is_mut
is_root_mut := scope.is_selector_root_mutable(c.table, node.cond)
// smartcast either if the value is immutable or if the mut argument is explicitly given
if (!is_root_mut && !is_mut) || node.is_mut {
sum_type_casts << expr_type
scope.register_struct_field(ast.ScopeStructField{
struct_type: node.cond.expr_type
name: node.cond.field_name
typ: node.cond_type
sum_type_cast: expr_type
sum_type_casts: sum_type_casts
pos: node.cond.pos
})
}
}
ast.Ident {
mut is_mut := false
mut sum_type_casts := []table.Type{}
mut is_already_casted := false
if v := scope.find_var(node.cond.name) {
is_mut = v.is_mut
sum_type_casts << v.sum_type_casts
is_already_casted = v.pos.pos == node.cond.pos.pos
}
// smartcast either if the value is immutable or if the mut argument is explicitly given
if !is_mut || node.is_mut {
if (!is_mut || node.is_mut) && !is_already_casted {
sum_type_casts << expr_type
scope.register(node.var_name, ast.Var{
name: node.var_name
typ: node.cond_type
pos: node.cond.pos
is_used: true
is_mut: node.is_mut
sum_type_cast: expr_type
sum_type_casts: sum_type_casts
})
}
}
@ -3823,38 +3833,46 @@ pub fn (mut c Checker) if_expr(mut node ast.IfExpr) table.Type {
mut is_mut := false
mut scope := c.file.scope.innermost(branch.body_pos.pos)
if mut infix.left is ast.Ident {
mut sum_type_casts := []table.Type{}
if v := scope.find_var(infix.left.name) {
is_mut = v.is_mut
sum_type_casts << v.sum_type_casts
}
// smartcast either if the value is immutable or if the mut argument is explicitly given
if (!is_mut || branch.is_mut_name) &&
left_sym.kind == .union_sum_type {
sum_type_casts << right_expr.typ
scope.register(branch.left_as_name, ast.Var{
name: branch.left_as_name
typ: infix.left_type
sum_type_cast: right_expr.typ
sum_type_casts: sum_type_casts
pos: infix.left.pos
is_used: true
is_mut: is_mut
})
}
} else if mut infix.left is ast.SelectorExpr {
mut sum_type_casts := []table.Type{}
expr_sym := c.table.get_type_symbol(infix.left.expr_type)
field := c.table.struct_find_field(expr_sym, infix.left.field_name) or {
table.Field{}
}
if field := c.table.struct_find_field(expr_sym, infix.left.field_name) {
is_mut = field.is_mut
}
if field := scope.find_struct_field(infix.left.expr_type,
infix.left.field_name) {
sum_type_casts << field.sum_type_casts
}
is_root_mut := scope.is_selector_root_mutable(c.table,
infix.left)
// smartcast either if the value is immutable or if the mut argument is explicitly given
if ((!is_root_mut && !is_mut) ||
branch.is_mut_name) &&
left_sym.kind == .union_sum_type {
sum_type_casts << right_expr.typ
scope.register_struct_field(ast.ScopeStructField{
struct_type: infix.left.expr_type
name: infix.left.field_name
typ: infix.left_type
sum_type_cast: right_expr.typ
sum_type_casts: sum_type_casts
pos: infix.left.pos
})
}

View File

@ -0,0 +1,6 @@
vlib/v/checker/tests/sum_type_assign_non_variant_err.vv:11:6: error: cannot assign to `w`: expected `Stmt`, not `IfExpr`
9 | fn main() {
10 | mut w := Stmt{}
11 | w = IfExpr{}
| ~~~~~~~~
12 | }

View File

@ -0,0 +1,12 @@
__type Expr = IfExpr | CallExpr | MatchExpr
struct MatchExpr {}
struct IfExpr {}
struct CallExpr {}
__type Stmt = Expr | AnotherThing
struct AnotherThing {}
fn main() {
mut w := Stmt{}
w = IfExpr{}
}

View File

@ -1301,7 +1301,7 @@ fn (mut g Gen) union_expr_with_cast(expr ast.Expr, got_type table.Type, expected
scope := g.file.scope.innermost(expr.position().pos)
if expr is ast.Ident {
if v := scope.find_var(expr.name) {
if v.sum_type_cast != 0 {
if v.sum_type_casts.len > 0 {
is_already_sum_type = true
}
}
@ -2567,12 +2567,17 @@ fn (mut g Gen) expr(node ast.Expr) {
scope := g.file.scope.innermost(node.pos.pos)
if field := scope.find_struct_field(node.expr_type, node.field_name) {
// union sum type deref
for i, typ in field.sum_type_casts {
g.write('(*')
cast_sym := g.table.get_type_symbol(field.sum_type_cast)
cast_sym := g.table.get_type_symbol(typ)
if i != 0 {
sum_type_deref_field += ').'
}
if cast_sym.info is table.Aggregate as sym_info {
sum_type_deref_field = '_${sym_info.types[g.aggregate_type_idx]}'
sum_type_deref_field += '_${sym_info.types[g.aggregate_type_idx]}'
} else {
sum_type_deref_field = '_$field.sum_type_cast'
sum_type_deref_field += '_$typ'
}
}
}
}
@ -3403,13 +3408,22 @@ fn (mut g Gen) ident(node ast.Ident) {
}
scope := g.file.scope.innermost(node.pos.pos)
if v := scope.find_var(node.name) {
if v.sum_type_cast != 0 {
if v.sum_type_casts.len > 0 {
if !prevent_sum_type_unwrapping_once {
sym := g.table.get_type_symbol(v.sum_type_cast)
if sym.info is table.Aggregate as sym_info {
g.write('(*${name}._${sym_info.types[g.aggregate_type_idx]})')
for _ in v.sum_type_casts {
g.write('(*')
}
for i, typ in v.sum_type_casts {
cast_sym := g.table.get_type_symbol(typ)
if i == 0 {
g.write(name)
}
if cast_sym.info is table.Aggregate as sym_info {
g.write('._${sym_info.types[g.aggregate_type_idx]}')
} else {
g.write('(*${name}._$v.sum_type_cast)')
g.write('._$typ')
}
g.write(')')
}
return
}
@ -4645,7 +4659,7 @@ fn (mut g Gen) write_types(types []table.TypeSymbol) {
}
g.type_definitions.writeln('typedef struct {')
g.type_definitions.writeln(' union {')
for variant in g.table.get_union_sum_type_variants(it) {
for variant in it.variants {
g.type_definitions.writeln(' ${g.typ(variant.to_ptr())} _$variant.idx();')
}
g.type_definitions.writeln(' };')

View File

@ -853,18 +853,6 @@ pub:
variants []Type
}
pub fn (table &Table) get_union_sum_type_variants(sum_type UnionSumType) []Type {
mut variants := []Type{}
for variant in sum_type.variants {
sym := table.get_type_symbol(variant)
if sym.info is UnionSumType as sym_info {
variants << table.get_union_sum_type_variants(sym_info)
}
variants << variant
}
return variants
}
pub fn (table &Table) type_to_str(t Type) string {
sym := table.get_type_symbol(t)
mut res := sym.source_name

View File

@ -738,9 +738,6 @@ pub fn (table &Table) sumtype_has_variant(parent Type, variant Type) bool {
if v.idx() == variant.idx() {
return true
}
if table.sumtype_has_variant(v, variant) {
return true
}
}
}
return false

View File

@ -106,15 +106,49 @@ fn test_converting_down() {
assert res[1].name == 'three'
}
struct NodeWrapper {
node Node
}
fn test_nested_sumtype_selector() {
c := NodeWrapper{Node(Expr(IfExpr{pos: 1}))}
if c.node is Expr {
if c.node is IfExpr {
assert c.node.pos == 1
}
else {
assert false
}
}
else {
assert false
}
}
fn test_nested_sumtype_match_selector() {
c := NodeWrapper{Node(Expr(IfExpr{pos: 1}))}
match union c.node {
Expr {
match union c.node {
IfExpr {
assert c.node.pos == 1
}
else {
assert false
}
}
}
else {
assert false
}
}
}
fn test_nested_sumtype() {
mut a := Node{}
mut b := Node{}
a = StructDecl{pos: 1}
b = IfExpr{pos: 1}
c := Node(Expr(IfExpr{pos:1}))
if c is Expr {
if c is IfExpr {
assert true
assert c.pos == 1
}
else {
assert false
@ -125,6 +159,25 @@ fn test_nested_sumtype() {
}
}
fn test_nested_sumtype_match() {
c := Node(Expr(IfExpr{pos: 1}))
match union c {
Expr {
match union c {
IfExpr {
assert c.pos == 1
}
else {
assert false
}
}
}
else {
assert false
}
}
}
__type Abc = int | string
fn test_string_cast_to_sumtype() {