std::vector tokens_; Token getToken() { mtx_.lock(); if (tokens_.empty()) tokens_.push_back(Token::create()); Token t = std::move(tokens_.back()); tokens_.pop_back(); facilities of the bathroom itself. TokenPool’s mtx_ protects its vector tokens_. Every access (read or write) to tokens_ must be done under a lock on mtx_. This is an invariant that must be preserved getToken() { mtx_.lock(); if (tokens_.empty()) tokens_.push_back(Token::create()); Token t = std::move(tokens_.back()); tokens_.pop_back(); mtx_.unlock();

Sequences Status: prototype implementation constexpr auto t1 = ^^{ a + /* hi! */ b }; // three tokens static_assert(std::is_same_v); constexpr auto t2 = ^^{ a += ( }; constexpr auto strings and integrals, creates an identifier • \tokens( expr ) expands another token sequence •Inside any consteval function: • queue_injection( tokens_expr ) injects a token sequence into the current // Same as: int x = 42; typename[:^char:] c = '*'; // Same as: char c = '*';Angle of Attack Tokens, tokens everywhere… •P3294 (Injection with Token Sequences) a game changer for generation • Lennon/McCartney

name = identifier_of(proto); queue_injection(^^{ class \id(name) { public: \tokens(make_interface_functions(proto)) virtual ~\id(name)() = default; \id(name)() = default; \id(name)(\id(name) (is_nonspecial_member_function(mem)) { ret = ^^{ \tokens(ret) virtual [:\(return_type_of(mem)):] \id(identifier_of(mem)) (\tokens(parameter_list_of(mem))) = 0; }; }

functions, types, treesParser In a compiler: tokens -> parser -> syntax tree In a web browser: text -> JSON parser -> JS object parse(text or tokens) -> value or errorParser Combinators Create a stream #[proc_macro] pub fn my_macro(input: TokenStream) -> TokenStream { /*...*/ } my_macro!(tokens); #[derive(Clone, Debug, my_macro)] struct MyStruct;Rust Macros – Overview Macro rules matches a

use the same sequence of tokens. They must generally refer to the same other entities. Sometimes they may refer to different constants with the same value. Linkage name: tokens, values, linkage namesLorem

Phase 5 Phase 6 Phase 7 Phase 8 Phase 9 • the source file is decomposed into preprocessing tokens, sequences of whitespace characters, and comments • each comment is replaced by one whitespace Phase 7 Phase 8 Phase 9 • each preprocessing token is converted into a token • the resulting tokens are syntactically and semantically analyzed and translated as a translation unitCopyright © 2020

receiver … time passes… 74 Some senders have stop sources. “I’ll do my best!” They pass stop tokens to the operation state. Cancellation details are internal to algorithms. “Hey, receiver! I’ve THREE-WAY HANDSHAKE OpState Caller Receiver “Please stop.” “I’ve stopped.”76 SENDERS PASS STOP TOKENS TO CHILDREN VIA RECEIVERS when_all then then then schedule schedule schedule connect X 3 stop_source

server authorization is done with JWT. jwt_secret is a random string used to generate authentication tokens. You can change it safely anytime (in fact it is a good practice). The change will just force users value disk_authorize_timeout is not currently used. File trans- fers are authorized with their own tokens, generated with the secret updown_secret. This value should be different from the above jwt_secret user optional arguments: -h, --help show this help message and exit -c, --clean Remove user and tokens for all remotes -p [PASSWORD], --password [PASSWORD] User password. Use double quotes if password

server authorization is done with JWT. jwt_secret is a random string used to generate authentication tokens. You can change it safely anytime (in fact it is a good practice). The change will just force users value disk_authorize_timeout is not currently used. File trans- fers are authorized with their own tokens, generated with the secret updown_secret. This value should be different from the above jwt_secret user optional arguments: -h, --help show this help message and exit -c, --clean Remove user and tokens for all remotes -p [PASSWORD], --password [PASSWORD] User password. Use double quotes if password

server authorization is done with JWT. jwt_secret is a random string used to generate authentication tokens. You can change it safely anytime (in fact it is a good practice). The change will just force users value disk_authorize_timeout is not currently used. File trans- fers are authorized with their own tokens, generated with the secret updown_secret. This value should be different from the above jwt_secret user optional arguments: -h, --help show this help message and exit -c, --clean Remove user and tokens for all remotes -p [PASSWORD], --password [PASSWORD] User password. Use double quotes if password