Finch/boot/ast.fch
Nexoniarz 083d66c82b boot: maps, for k, v in, for i, x in
map[K]V, [:] and ["a": 1] literals, m[k] reads and writes (m[k] += 1 starts from
zero), has/get/remove/clear/keys/values, .len, copy and printing, and a loop over
a map that stops with an error when it adds keys. for i, x in list gives the
index too.

boot.sh: 17 passed, 0 failed, 5 skipped (all five import C).
2026-10-25 19:13:46 +01:00

109 lines
2.7 KiB
Text

// The syntax tree of the self-hosted compiler.
// A type as written or resolved.
// kind: "void" "int" "bool" "char" "float" "str" "null" "ptr" "array" "named" "struct"
// elem: the element of an array or the target of a ptr (zero or one entry)
// name, module: structs ("" module = the main file)
struct Type {
str kind
[]Type elem
str name
str module
}
fn simple(str kind) -> Type {
return Type(kind: kind)
}
fn arrayOf(Type t) -> Type {
out := Type(kind: "array")
out.elem.push(t)
return out
}
// map[K]V: elem holds the key, then the value
fn mapOf(Type k, Type v) -> Type {
out := Type(kind: "map")
out.elem.push(k)
out.elem.push(v)
return out
}
fn ptrTo(Type t) -> Type {
out := Type(kind: "ptr")
out.elem.push(t)
return out
}
fn same(Type a, Type b) -> bool {
if a.kind != b.kind {
return false
}
if a.kind == "struct" || a.kind == "named" {
return a.name == b.name && a.module == b.module
}
if a.kind == "array" || a.kind == "ptr" || a.kind == "map" {
if a.elem.len != b.elem.len {
return false
}
for i in 0..a.elem.len {
if !same(a.elem[i], b.elem[i]) {
return false
}
}
return true
}
return true
}
fn show(Type t) -> str {
if t.kind == "array" {
return "[]" + show(t.elem[0])
}
if t.kind == "map" {
return "map[" + show(t.elem[0]) + "]" + show(t.elem[1])
}
if t.kind == "ptr" {
if t.elem.len == 0 {
return "ptr"
}
return "ptr[" + show(t.elem[0]) + "]"
}
if t.kind == "struct" || t.kind == "named" {
if t.module.len > 0 {
return t.module + "." + t.name
}
return t.name
}
if t.kind == "void" {
return "nothing"
}
return t.kind
}
// One node of the tree, for expressions, statements, functions and structs alike.
// expressions: int float str char bool null var unary binary call member index array method
// statements: decl assign expr if while for each return break continue block
// top level: fn param struct field
struct Node {
str kind
str name // identifier, operator, callee, field or method name
str recv // fn Point.move(...): "Point"; empty for a plain function
str text // literal text
Type ty // declared type (decl, param, field, fn result)
bool flag // decl: has a type; or: the right side is a { block }
bool fallible // fn: -> T! or -> !
[]Node kids
[]str names // named arguments: Point(x: 1)
int line
int col
int file
}
struct Program {
str module
str path
[]str imports // Finch modules
[]Node structs
[]Node fns
}