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|
const std = @import("std");
pub const TokenizeError = error{
UnexpectedEnd,
InvalidCharacter,
};
pub const TokenKind = enum {
end,
dot,
bracket_left,
bracket_right,
number,
};
pub const Token = union(TokenKind) {
end,
dot,
bracket_left,
bracket_right,
number: i64,
pub fn kind(self: @This()) TokenKind {
return self;
}
};
pub fn tokenize(allocator: std.mem.Allocator, reader: *std.Io.Reader) ![]Token {
var tokens = try std.array_list.Aligned(Token, null).initCapacity(allocator, 16);
while (true) {
const c = reader.takeByte() catch |err| switch (err) {
error.EndOfStream => break,
error.ReadFailed => return error.ReadFailed,
};
switch (c) {
'.' => try tokens.append(allocator, .dot),
'[' => try tokens.append(allocator, .bracket_left),
']' => try tokens.append(allocator, .bracket_right),
else => {
if (std.ascii.isDigit(c)) {
try tokens.append(allocator, .{ .number = (c - '0') });
} else {
return error.InvalidCharacter;
}
},
}
}
if (tokens.items.len == 0) {
return error.UnexpectedEnd;
}
try tokens.append(allocator, .end);
return tokens.toOwnedSlice(allocator);
}
|
