// heading.

// under returns the expanded underlying type of n0; possibly by following
// forward chains of named types. If an underlying type is found, resolve
// the chain by setting the underlying type for each defined type in the
// chain before returning it. If no underlying type is found or a cycle
// is detected, the result is Typ[Invalid]. If a cycle is detected and

	// Passthrough is the name of the virtual host used to forward traffic to the
	// PassthroughCluster
	Passthrough = "allow_any"

	// PassthroughFilterChain to catch traffic that doesn't match other filter chains.
	PassthroughFilterChain = "PassthroughFilterChain"

	// Inbound pass through cluster need to the bind the loopback ip address for the security and loop avoidance.
	InboundPassthroughCluster = "InboundPassthroughCluster"

	// Create a new chain for redirecting outbound traffic to the common Envoy port.
	// In both chains, '-j RETURN' bypasses Envoy and '-j ISTIOREDIRECT'
	// redirects to Envoy.
	cfg.ruleBuilder.AppendRule(iptableslog.UndefinedCommand,
		constants.ISTIOREDIRECT, constants.NAT, "-p", constants.TCP, "-j", constants.REDIRECT, "--to-ports", cfg.cfg.ProxyPort)

// heading.

// under returns the expanded underlying type of n0; possibly by following
// forward chains of named types. If an underlying type is found, resolve
// the chain by setting the underlying type for each defined type in the
// chain before returning it. If no underlying type is found or a cycle
// is detected, the result is Typ[Invalid]. If a cycle is detected and

					ok: []string{"dns:.foo.com"},
				},
			},
		},
		leaf: leafSpec{
			sans: []string{"dns:foo.example.com"},
		},
		noOpenSSL: true, // OpenSSL's chain building is not informed by constraints.
	},

	// #24: when multiple roots are valid, chain building can avoid roots
	// with incompatible constraints.
	{
		roots: []constraintsSpec{
			{},
			{
				ok: []string{"dns:foo.com"},
			},
		},

				// location so we give the some hint as to where the
				// inlining happened that led to this instruction. So for
				// example, suppose we have the following (inlined) call
				// chains for this instruction:
				//   F1->G->H
				//   F2->G->H
				// We could tag the instructions from the first call with
				// F1 and instructions from the second call with F2. But

	// BuildHandlerChainFunc allows you to build custom handler chains by decorating the apiHandler.
	BuildHandlerChainFunc func(apiHandler http.Handler, c *Config) (secure http.Handler)
	// NonLongRunningRequestWaitGroup allows you to wait for all chain
	// handlers associated with non long-running requests
	// to complete while the server is shuting down.

	fs.BoolVar(&c.MakeIPTablesUtilChains, "make-iptables-util-chains", c.MakeIPTablesUtilChains, "If true, kubelet will ensure iptables utility rules are present on host.")

!!! check "vérifier"
    Comme vous l'avez remarqué, la valeur reçue par la fonction (et renvoyée ensuite) est `3`,
    en tant qu'entier (`int`) Python, pas la chaîne de caractères (`string`) `"3"`.

    Grâce aux déclarations de types, **FastAPI** fournit du
    <abbr title="conversion de la chaîne de caractères venant de la requête HTTP en données Python">"parsing"</abbr> automatique.

## Validation de données

	dataqsiz uint           // size of the circular queue
	buf      unsafe.Pointer // points to an array of dataqsiz elements
	elemsize uint16
	closed   uint32
	timer    *timer // timer feeding this chan
	elemtype *_type // element type
	sendx    uint   // send index
	recvx    uint   // receive index
	recvq    waitq  // list of recv waiters
	sendq    waitq  // list of send waiters