343 lines
9.1 KiB
Plaintext
343 lines
9.1 KiB
Plaintext
import "@std"
|
|
import "@std/mem"
|
|
import "@std/strmap"
|
|
import "@std/enums/enummap"
|
|
import "@std/arraylist"
|
|
|
|
import "@source/strpool"
|
|
|
|
ScanError :: struct {
|
|
code ErrorCode
|
|
end usize
|
|
}
|
|
|
|
ErrorCode :: enum {
|
|
invalid_character,
|
|
float_must_end_with_digit,
|
|
unterminated_string,
|
|
}
|
|
|
|
ErrorDetails :: struct {
|
|
name []u8
|
|
message []u8
|
|
}
|
|
|
|
error_msg_map std.EnumMap(ErrorCode, ErrorDetails) :: enummap.init({
|
|
invalid_character = ErrorDetails {
|
|
name = "L0",
|
|
message = "invalid character",
|
|
},
|
|
float_must_end_with_digit = ErrorDetails {
|
|
name = "L1",
|
|
message = "float must end with a digit",
|
|
},
|
|
})
|
|
|
|
keywords std.StringMap(TokenKind) :: strmap.init([
|
|
{ "proc", .proc },
|
|
{ "return", .return },
|
|
{ "if", .if },
|
|
{ "for", .for },
|
|
{ "else", .else },
|
|
{ "while", .while },
|
|
])
|
|
|
|
Diagnostic :: struct {
|
|
token TokenId
|
|
code ErrorCode
|
|
}
|
|
|
|
State :: struct {
|
|
tokens std.ArrayList(Token)
|
|
diagnostics std.ArrayList(Diagnostic)
|
|
}
|
|
|
|
init proc(allocator mem.Allocator) State {
|
|
return State {
|
|
tokens = arraylist.init(allocator),
|
|
diagnostics = arraylist.init(allocator),
|
|
}
|
|
}
|
|
|
|
deinit proc(state @mut State) void {
|
|
arraylist.deinit(&state.tokens)
|
|
arraylist.deinit(&state.diagnostics)
|
|
}
|
|
|
|
scan proc(state @mut State, program []u8) void ! (mem.AllocError | strpool.InternError) {
|
|
diagnostics :: &state.diagnostics
|
|
|
|
cursor := 0
|
|
while cursor < program.len {
|
|
char :: program[cursor]
|
|
|
|
# whitespace
|
|
if char == '\n' {
|
|
try add_token(state, Token{ start = cursor, kind = .newline })
|
|
cursor += 1
|
|
continue
|
|
} else if is_whitespace(char) {
|
|
cursor += 1
|
|
continue
|
|
}
|
|
|
|
# comments
|
|
if char == '#' {
|
|
while (cursor < program.len and program[cursor] != '\n') cursor += 1
|
|
cursor += 1 # also skip newline
|
|
continue
|
|
}
|
|
|
|
# identifiers and keywords
|
|
if is_alpha(char) or char == '_' {
|
|
start :: cursor
|
|
result :: scan_ident(start, program)
|
|
try add_token(state, Token{
|
|
start = start,
|
|
kind = result.kind,
|
|
str_id = result.str_id,
|
|
})
|
|
cursor = result.end
|
|
continue
|
|
}
|
|
|
|
# numeric literals
|
|
if is_digit(char) {
|
|
start :: cursor
|
|
result :: scan_number(start, program) catch |err| {
|
|
token :: token_id(state.tokens.items.len)
|
|
try add_token(state, Token{ start = start, kind = .invalid })
|
|
try arraylist.append(diagnostics, Diagnostic{ token = token, code = err.code })
|
|
cursor = err.end
|
|
continue
|
|
}
|
|
|
|
kind :: if (result.has_decimal) .float else .int
|
|
try add_token(state, Token{ start = start, kind = kind })
|
|
cursor = result.end
|
|
continue
|
|
}
|
|
|
|
# string literals
|
|
if char == '"' {
|
|
start :: cursor
|
|
result :: scan_string(start, program) catch |err| {
|
|
token :: token_id(state.tokens.items.len)
|
|
try add_token(state, Token{ start = start, kind = .invalid })
|
|
try arraylist.append(diagnostics, Diagnostic{ token = token, code = err.code })
|
|
cursor = err.end
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = start, kind = .string })
|
|
cursor = result.end
|
|
continue
|
|
}
|
|
|
|
# immutable decl, mutable decl, or single colon
|
|
if char == ':' {
|
|
if cursor + 1 < program.len and program[cursor + 1] == ':' {
|
|
try add_token(state, Token{ start = cursor, kind = .double_colon })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
if cursor + 1 < program.len and program[cursor + 1] == '=' {
|
|
try add_token(state, Token{ start = cursor, kind = .colon_equal })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .colon })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
|
|
# compound arithmetic assignment
|
|
if char == '+' {
|
|
if cursor + 1 < program.len and program[cursor + 1] == '=' {
|
|
try add_token(state, Token{ start = cursor, kind = .plus_equal })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .plus })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
if char == '-' {
|
|
if cursor + 1 < program.len and program[cursor + 1] == '=' {
|
|
try add_token(state, Token{ start = cursor, kind = .minus_equal })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .minus })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
if char == '*' {
|
|
if cursor + 1 < program.len and program[cursor + 1] == '=' {
|
|
try add_token(state, Token{ start = cursor, kind = .star_equal })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .star })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
if char == '/' {
|
|
if cursor + 1 < program.len and program[cursor + 1] == '=' {
|
|
try add_token(state, Token{ start = cursor, kind = .slash_equal })
|
|
cursor += 2
|
|
continue
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .slash })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
|
|
# single character tokens
|
|
kind ?TokenKind :: match char {
|
|
'=': .equal
|
|
',': .comma
|
|
'(': .open_paren
|
|
')': .close_paren
|
|
'{': .open_curly
|
|
'}': .close_curly
|
|
else: null
|
|
}
|
|
|
|
if (kind) |k| {
|
|
try add_token(state, Token{ start = cursor, kind = k })
|
|
cursor += 1
|
|
continue
|
|
}
|
|
|
|
# invalid character
|
|
token :: token_id(state.tokens.items.len)
|
|
try add_token(state, Token{ start = cursor, kind = .invalid })
|
|
try arraylist.append(diagnostics, Diagnostic{ token = token, code = .invalid_character })
|
|
cursor += 1
|
|
}
|
|
|
|
try add_token(state, Token{ start = cursor, kind = .eof })
|
|
}
|
|
|
|
ScanIdentResult :: struct {
|
|
end usize
|
|
kind TokenKind
|
|
str_id strpool.StringId
|
|
}
|
|
|
|
scan_ident proc(start usize, program []u8) ScanIdentResult {
|
|
cursor := start + 1
|
|
|
|
# scan whole identifier
|
|
while (cursor < program.len and (
|
|
is_alpha(program[cursor]) or
|
|
is_digit(program[cursor]) or
|
|
program[cursor] == '_'
|
|
)) cursor += 1
|
|
|
|
kind :: strmap.get(&keywords, program[start..cursor]) orelse .ident
|
|
|
|
# don't intern keywords (already O(1) lookup via token kind)
|
|
str_id :: if (kind == .ident)
|
|
strpool.intern(&strpool.STRINGS, program[start..cursor]) catch strpool.NO_STR
|
|
else
|
|
strpool.NO_STR
|
|
|
|
return ScanIdentResult{
|
|
end = cursor,
|
|
kind = kind,
|
|
str_id = str_id,
|
|
}
|
|
}
|
|
|
|
ScanNumResult :: struct {
|
|
end usize
|
|
has_decimal bool
|
|
}
|
|
|
|
scan_number proc(start usize, program []u8) ScanNumResult ! ScanError {
|
|
cursor := start
|
|
has_decimal := false
|
|
|
|
# scan integer part
|
|
while (cursor < program.len and is_digit(program[cursor])) cursor += 1
|
|
|
|
# check for decimal
|
|
if cursor < program.len and program[cursor] == '.' {
|
|
has_decimal = true
|
|
cursor += 1
|
|
}
|
|
|
|
# assert non-terminating decimal
|
|
if has_decimal and (cursor >= program.len or !is_digit(program[cursor])) {
|
|
return ScanError{
|
|
code = .float_must_end_with_digit,
|
|
end = cursor,
|
|
}
|
|
}
|
|
|
|
# scan fractional part
|
|
while (cursor < program.len and is_digit(program[cursor])) cursor += 1
|
|
|
|
return ScanNumResult{
|
|
end = cursor,
|
|
has_decimal = has_decimal,
|
|
}
|
|
}
|
|
|
|
ScanStrResult :: struct { end usize }
|
|
|
|
scan_string proc(start usize, program []u8) ScanStrResult ! ScanError {
|
|
cursor := start + 1 # skip first `"`
|
|
|
|
# scan entire string
|
|
while cursor < program.len and program[cursor] != '"' and program[cursor] != '\n' : cursor += 1 {
|
|
# ignore escaped characters
|
|
if (program[cursor] == '\\' and cursor + 1 < program.len) cursor += 1
|
|
}
|
|
|
|
# assert string terminal
|
|
if (cursor >= program.len or program[cursor] != '"') return ScanError{
|
|
code = .unterminated_string,
|
|
end = cursor,
|
|
}
|
|
|
|
return ScanStrResult{
|
|
end = cursor + 1, # skip last `"`
|
|
}
|
|
}
|
|
|
|
@hide
|
|
is_whitespace proc(char u8) bool {
|
|
return char == ' ' or char == '\t' or char == '\n' or char == '\r'
|
|
}
|
|
|
|
@hide
|
|
is_alpha proc(char u8) bool {
|
|
return match char {
|
|
'a'..='z', 'A'..='Z': true
|
|
else: false
|
|
}
|
|
}
|
|
|
|
@hide
|
|
is_digit proc(char u8) bool {
|
|
return match char {
|
|
'0'..='9': true
|
|
else: false
|
|
}
|
|
}
|
|
|
|
@hide
|
|
add_token proc(state @mut State, token Token) void ! mem.AllocError {
|
|
_ = token_id(state.tokens.items.len)
|
|
try arraylist.append(&state.tokens, token)
|
|
}
|