import (
	"bytes"
	"fmt"
	"sort"
	"strings"
)

const (
	// Upper limit for recursion depth. Used to catch infinite recursions
	// due to implementation issues (e.g., see issues go.dev/issue/48619, go.dev/issue/48656).
	unificationDepthLimit = 50

	// Whether to panic when unificationDepthLimit is reached.
	// If disabled, a recursion depth overflow results in a (quiet)
	// unification failure.
	panicAtUnificationDepthLimit = true

import (
	"bytes"
	"fmt"
	"sort"
	"strings"
)

const (
	// Upper limit for recursion depth. Used to catch infinite recursions
	// due to implementation issues (e.g., see issues go.dev/issue/48619, go.dev/issue/48656).
	unificationDepthLimit = 50

	// Whether to panic when unificationDepthLimit is reached.
	// If disabled, a recursion depth overflow results in a (quiet)
	// unification failure.
	panicAtUnificationDepthLimit = true

// a signature, and the hash value of t must depend only on t's index and
// constraint: signatures are considered identical modulo type parameter
// renaming. To avoid infinite recursion, we only hash the type parameter
// index, and rely on types.Identical to handle signatures where constraints
// are not identical.
//
// Otherwise the hash of t depends only on t's pointer identity.

		return subst.tuple(t)

	case *Signature:
		// Preserve the receiver: it is handled during *Interface and *Named type
		// substitution.
		//
		// Naively doing the substitution here can lead to an infinite recursion in
		// the case where the receiver is an interface. For example, consider the
		// following declaration:
		//
		//  type T[A any] struct { f interface{ m() } }
		//

		return subst.tuple(t)

	case *Signature:
		// Preserve the receiver: it is handled during *Interface and *Named type
		// substitution.
		//
		// Naively doing the substitution here can lead to an infinite recursion in
		// the case where the receiver is an interface. For example, consider the
		// following declaration:
		//
		//  type T[A any] struct { f interface{ m() } }
		//

	}

	// An infinitely expanding interface (due to a cycle) is detected
	// elsewhere (Checker.validType), so here we simply assume we only
	// have valid interfaces. Mark the interface as complete to avoid
	// infinite recursion if the validType check occurs later for some
	// reason.
	ityp.tset = &_TypeSet{terms: allTermlist} // TODO(gri) is this sufficient?

	var unionSets map[*Union]*_TypeSet
	if check != nil {

	}

	// An infinitely expanding interface (due to a cycle) is detected
	// elsewhere (Checker.validType), so here we simply assume we only
	// have valid interfaces. Mark the interface as complete to avoid
	// infinite recursion if the validType check occurs later for some
	// reason.
	ityp.tset = &_TypeSet{terms: allTermlist} // TODO(gri) is this sufficient?

	var unionSets map[*Union]*_TypeSet
	if check != nil {

	}

	// SetConstraint can't be called if the constraint type is not yet complete.
	// When type params are created in the 'P' case of (*importReader).obj(),
	// the associated constraint type may not be complete due to recursion.
	// Therefore, we defer calling SetConstraint there, and call it here instead
	// after all types are complete.
	for _, d := range p.later {
		d.t.SetConstraint(d.constraint)
	}

        String fullMessage = (message != null) ? message : "";

        // To break out of possible endless loop when getCause returns "this", or dejaVu for n-level recursion (n>1)
        Set<Throwable> dejaVu = Collections.newSetFromMap(new IdentityHashMap<>());
        for (Throwable t = exception; t != null && t != t.getCause(); t = t.getCause()) {

				//        m() interface{T}
				//    }
				//
				// If two such (differently named) interfaces are compared,
				// endless recursion occurs if the cycle is not detected.
				//
				// If x and y were compared before, they must be equal
				// (if they were not, the recursion would have stopped);
				// search the ifacePair stack for the same pair.
				//
				// This is a quadratic algorithm, but in practice these stacks