## On Asynchrony in Name-Passing Calculi (1998)

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Venue: | In |

Citations: | 94 - 14 self |

### BibTeX

@INPROCEEDINGS{Merro98onasynchrony,

author = {Massimo Merro and Davide Sangiorgi},

title = {On Asynchrony in Name-Passing Calculi},

booktitle = {In},

year = {1998},

pages = {856--867},

publisher = {Springer-Verlag}

}

### Years of Citing Articles

### OpenURL

### Abstract

The asynchronous pi-calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict, Join, and Blue calculus. However, at a closer inspection, these languages are based on an even simpler calculus, called Local (L), where: (a) only the output capability of names may be transmitted; (b) there is no matching or similar constructs for testing equality between names. We study the basic operational and algebraic theory of Lpi. We focus on bisimulation-based behavioural equivalences, precisely on barbed congruence. We prove two coinductive characterisations of barbed congruence in Lpi, and some basic algebraic laws. We then show applications of this theory, including: the derivability of delayed input; the correctness of an optimisation of the encoding of call-by-name lambda-calculus; the validity of some laws for Join.

### Citations

1153 |
Actors: A Model of Concurrent Computation in Distributed Systems
- Agha
- 1986
(Show Context)
Citation Context ...t and distributed programming languages, because they are easier to implement and they are closer to the communication primitives ooeered by available distributed systems (see also Agha's actor model =-=[2]-=-). The asynchronous -calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict [33], Join [13],s1 [3], and the Blue calculus [11]. However... |

1064 | Bigraphs and mobile processes
- Jensen, Milner
- 2003
(Show Context)
Citation Context ... oe to P , with the usual renaming convention to avoid captures. Parallel composition has the lowest precedence among the operators. The labeled transition system is the usual one (in the late style, =-=[27, 38]-=-). Transition are of the form P \Gamma! P 0 , where actionscan be:s(interaction), a(b) (input), ab (free output) and (b)ab (bound output, that is the emission of a private name b at a). In these actio... |

634 |
Compiling with Continuations
- Appel
- 1992
(Show Context)
Citation Context ...ness of CPS axioms Thielecke studies the target calculi of Continuation Passing Style transforms [39]. For this, he introduces a CPS calculus, similar to the intermediate language of Appel's compiler =-=[5]-=-. The CPS calculus is very simple and low-level: only variables may be passed as arguments, moreover application is like a jump, with variables as argument. Thielecke gives an axiomatic semantics for ... |

490 | The chemical abstract machine
- Berry, Boudol
- 1990
(Show Context)
Citation Context ...dencies. This appears, for instance, in Abramsky's representation of Linear Logic proofs as -calculus processes [1, 6]. Non-blocking message reception has been studied by Bellin and Scott [6], Boudol =-=[10]-=-, Fu [14], Parrow and Victor [32], Yoshida [41] and van Breugel [40]. Bellin and Scott give a reduction semantics for a version of -calculus, proposed by Milner, where both message emission and messag... |

423 | A language with distributed scope
- Cardelli
- 1995
(Show Context)
Citation Context ...alogous 32 results for other #-calculi [49, 51]. In [33] L# is used to give a translational semantics of (an appropriate abstraction of) Cardelli's distributed object-based programming language Obliq =-=[12]-=-. The theory of L# (precisely a typed variant of Lemma 5.17) is used to prove the correctness of object migration. Finally, we are currently using L# to study termination for mobile processes [58]. Ac... |

375 | An Object Calculus for Asynchronous Communications
- Honda, Tokoro
- 1991
(Show Context)
Citation Context ...ocking. Formally, the output prex ab. P of -calculus is replaced with the simpler output particle ab, which has no continuation. The asynchronous -calculus has been rst introduced by Honda and Tokoro =-=[17]-=-, who showed that it is expressive enough to encode the (synchronous) -calculus. Asynchronous communications are interesting from the point of view of concurrent and distributed programming languages,... |

335 |
Functions as Processes
- Milner
- 1992
(Show Context)
Citation Context ...et: (j x. M j) p def = (v; x; q) i phvi j v(y; r). (x . y j q . r) j (j M j) q j One can prove results of operational correspondence and validity of fi-reduction for this encoding similar to those in =-=[24, 35]-=- for the call-by-name -calculus. (The modelling of strong reductions is a major motivation behind Fusion and Chi; indeed both calculi allows us to encode strong call-by-name -calculus [32, 14]). 6.4. ... |

282 |
The Polyadic -calculus: a Tutorial
- Milner
- 1993
(Show Context)
Citation Context ...utput are very dioeerent, and this dioeerence is observable insa and in -calculus. Law 4 is a distributivity law for replicated resources (a stronger 1 version of one of Milner's replication theorems =-=[22]-=-). The main inconvenience of barbed congruence is that it uses quantication over contexts in the denition, and this can make proofs of process equalities heavy. Against this, it is important to nd dir... |

272 |
Expressing Mobility in Process Algebras: First-order and Higher-order Paradigms
- Sangiorgi
- 1992
(Show Context)
Citation Context ...ith the closure under substitutions of early bisimilarity; in the asynchronous -calculus it coincides with the closure under substitutions of asynchronous early bisimilarity (on image-nite processes) =-=[4, 34]-=-. We prove two characterisations of barbed congruence in L (as usual, on image-nite processes). The rst is based on an embedding of L into a subcalculus where all names emitted are private. Barbed con... |

263 | Piet: A programming language based on the pi- calculus
- Pierce, Turner
- 1997
(Show Context)
Citation Context ...ilable distributed systems (see also Agha's actor model [2]). The asynchronous -calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict =-=[33]-=-, Join [13],s1 [3], and the Blue calculus [11]. However, at a closer inspection, these languages are based on an even simpler calculus, where: (a) the recipient of a name may only use it in output act... |

253 |
The Reflexive Chemical Abstract Machine and the Join calculus
- Fournet, Gonthier
- 1996
(Show Context)
Citation Context ...ributed systems (see also Agha's actor model [2]). The asynchronous -calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict [33], Join =-=[13]-=-,s1 [3], and the Blue calculus [11]. However, at a closer inspection, these languages are based on an even simpler calculus, where: (a) the recipient of a name may only use it in output actions; that ... |

233 | Barbed bisimulation
- Milner, Sangiorgi
- 1992
(Show Context)
Citation Context ... additional simplications (a) and (b). In this paper, we study the basic operational and algebraic theory of L. We focus on bisimulation-based behavioural equivalences, precisely on barbed congruence =-=[28]-=-. This equates processes that, very roughly, in all contexts give rise to the same patterns of interactions. Like other contextuallyde ned forms of bisimulation, barbed congruence is sensitive to the ... |

148 | On Reduction-Based Process Semantics
- Honda, Yoshida
- 1995
(Show Context)
Citation Context ...lso say that restriction (a) denes the location of a, and see L as a simple calculus of distributed objects. Studies of bisimulation-based behavioural equivalences for asynchronous mobile calculi are =-=[17, 19, 15, 4]-=-. In these theories, the most important algebraic law that is not in the theory of the synchronous -calculus is !a(x). ax = 0 Although this law is useful (it is used for instance by Pierce and Nestman... |

144 | Linearity and the Pi-Calculus
- Kobayashi, Pierce, et al.
- 1999
(Show Context)
Citation Context ...ve the same labels, therefore the problems given by restrictions (a) and (b) do not appear. Other studies of barbed congruence, or similar contextual-based bisimulations, for mobile processes include =-=[19, 20, 42, 14, 16]-=- (and, for a coordination language, [12]). [9] studies barbed congruence in synchronous -calculus with capability types and no matching, of which (a) and (b) are a special case. Our characterisations ... |

119 | An asynchronous model of locality, failure, and process mobility
- Amadio
- 1997
(Show Context)
Citation Context ...systems (see also Agha's actor model [2]). The asynchronous -calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict [33], Join [13],s1 =-=[3]-=-, and the Blue calculus [11]. However, at a closer inspection, these languages are based on an even simpler calculus, where: (a) the recipient of a name may only use it in output actions; that is, onl... |

115 | The fusion calculus: Expressiveness and symmetry in mobile processes
- Parrow, Victor
- 1998
(Show Context)
Citation Context ...s calculus message emission is non-blocking. Milner, Parrow, Victor and others have advocated also non-blocking message reception (which is among the motivations for the Update and the Fusion calculi =-=[31, 32]-=- and, implicitely for the Chi calculus [14]). Such a delayed input prex , written a(x)P , should allow the continuation P to evolve underneath the input guard, except for observable actions along x. T... |

100 | Decoding choice encodings
- Nestmann, Pierce
- 1996
(Show Context)
Citation Context ...t is not in the theory of the synchronous -calculus is !a(x). ax = 0 Although this law is useful (it is used for instance by Pierce and Nestmann to prove the correctness of an encoding of guarded sum =-=[29]-=-), it seems fair to say the restriction to asynchronous contexts does not aoeect much barbed congruence. By contrast, asynchrony has strong semantic consequences under of simplications (a) and (b). Co... |

87 | 7r-calculus, internal mobility and agent-passing calculi
- Sangiorgi
- 1996
(Show Context)
Citation Context ...ometimes use a more sophisticated form of link, which does not perform free outputs: the name sent at b is not x, but a link to x (this is the denition of links in calculi where all outputs are bound =-=[37]-=-). We call this a dynamic link process, written a ! b, and dened using recursion thus a ! b def = !a(x). (c)(bc j c ! x). Remark 1. The dynamic link process a ! b is not in L, but it is synchronous ea... |

82 | A typed language for distributed mobile processes
- Riely, Hennessy
- 1998
(Show Context)
Citation Context ...ve the same labels, therefore the problems given by restrictions (a) and (b) do not appear. Other studies of barbed congruence, or similar contextual-based bisimulations, for mobile processes include =-=[19, 20, 42, 14, 16]-=- (and, for a coordination language, [12]). [9] studies barbed congruence in synchronous -calculus with capability types and no matching, of which (a) and (b) are a special case. Our characterisations ... |

78 | An efficiency preorder for processes
- Arun-Kumar, Hennessy
- 1992
(Show Context)
Citation Context ...und bisimilar, written P # a Q, if P S Q for some asynchronous ground bisimulation S. Sometimes, it may be useful to count the number of silent moves performed by a process. The synchronous expansion =-=[5]-=-, written #, is an asymmetric variant of # such that P # Q holds if P # Q, and Q has at least as many #-moves as P . Similarly, one can define asynchronous expansion. Definition 3.5 (Expansions) . A r... |

77 | The Update Calculus
- Parrow, Victor
- 1997
(Show Context)
Citation Context ...s calculus message emission is non-blocking. Milner, Parrow, Victor and others have advocated also non-blocking message reception (which is among the motivations for the Update and the Fusion calculi =-=[31, 32]-=- and, implicitely for the Chi calculus [14]). Such a delayed input prex , written a(x)P , should allow the continuation P to evolve underneath the input guard, except for observable actions along x. T... |

72 | Categorical Structure of Continuation Passing Style
- Thielecke
- 1997
(Show Context)
Citation Context ...orems name a may not be exported. mobility and internal mobility (where only private names may be passed). (v) We prove that Thielecke's axiomatic semantics of the Continuation Passing Style calculus =-=[39]-=- is operationally sound. Calculi similar to L are discussed in [18, 7, 3, 41]. Some of the techniques we use in Section 4 are inspired by techniques in [38]. Characterisations of barbed congruence on ... |

66 | The π-calculus in direct style
- Boudol
- 1998
(Show Context)
Citation Context ...tor model [2]). The asynchronous -calculus is considered the basis of experimental programming languages (or proposal of programming languages) like Pict [33], Join [13],s1 [3], and the Blue calculus =-=[11]-=-. However, at a closer inspection, these languages are based on an even simpler calculus, where: (a) the recipient of a name may only use it in output actions; that is, only the output capability of n... |

65 |
On bisimulations for the asynchronous -calculus
- Amadio, Castellani, et al.
- 1996
(Show Context)
Citation Context ...lso say that restriction (a) denes the location of a, and see L as a simple calculus of distributed objects. Studies of bisimulation-based behavioural equivalences for asynchronous mobile calculi are =-=[17, 19, 15, 4]-=-. In these theories, the most important algebraic law that is not in the theory of the synchronous -calculus is !a(x). ax = 0 Although this law is useful (it is used for instance by Pierce and Nestman... |

63 | A hierarchy of equivalences for asynchronous calculi
- Fournet, Gonthier
- 1998
(Show Context)
Citation Context ..., for instance by Honda and Yoshida [26, 65], Kobayashi, Pierce, and Turner [29], Hennessy and Riely [21] and, for a coordination language, by Busi, Gorrieri, and Zavattaro [11]. Fournet and Gonthier =-=[17]-=- showed that the hypothesis of image-finitess can be dropped when characterising barbed congruence in asynchronous #-calculus. Boreale and Sangiorgi [8] have studied barbed congruence in synchronous #... |

61 | Graph types for monadic mobile processes
- Yoshida
- 1996
(Show Context)
Citation Context ...ve the same labels, therefore the problems given by restrictions (a) and (b) do not appear. Other studies of barbed congruence, or similar contextual-based bisimulations, for mobile processes include =-=[19, 20, 42, 14, 16]-=- (and, for a coordination language, [12]). [9] studies barbed congruence in synchronous -calculus with capability types and no matching, of which (a) and (b) are a special case. Our characterisations ... |

59 |
The Join-Calculus: a Calculus for Distributed Mobile Programming
- Fournet
- 1998
(Show Context)
Citation Context ...f follows from the compositionality of the encoding and the operational correspondence between a Join process P and its encoding #| P |#. Such an operational correspondence has already been proved in =-=[15]-=-. # Using this theorem and the theory of L# we can prove the following laws for the Join calculus: def a#x#=R in P | Q # =J (def a#x#=R in P ) | (def a#x#=R in Q) (13) def a#x#=b#x# in P # =J P{ b /a}... |

58 | The lazy lambda calculus in a concurrency scenario
- Sangiorgi
- 1994
(Show Context)
Citation Context ...et: (j x. M j) p def = (v; x; q) i phvi j v(y; r). (x . y j q . r) j (j M j) q j One can prove results of operational correspondence and validity of fi-reduction for this encoding similar to those in =-=[24, 35]-=- for the call-by-name -calculus. (The modelling of strong reductions is a major motivation behind Fusion and Chi; indeed both calculi allows us to encode strong call-by-name -calculus [32, 14]). 6.4. ... |

51 | The Join-Calculus
- Fournet
- 1998
(Show Context)
Citation Context ...lar to L are discussed in [18, 7, 3, 41]. Some of the techniques we use in Section 4 are inspired by techniques in [38]. Characterisations of barbed congruence on calculi for mobile processes include =-=[4, 8, 3]-=-. However, in these bisimilarity, matching transitions of processes have the same labels, therefore the problems given by restrictions (a) and (b) do not appear. Other studies of barbed congruence, or... |

50 | Implicit typing a la ML for the join-calculus
- Fournet, Laneve, et al.
- 1997
(Show Context)
Citation Context ...lculus [44, 20]. Concerning the CPS-calculus studied in Section 9.7, we are not aware of other proofs of Theorem 9.20. In Join and Blue calculus, polymorphic type systems a la ML have been introduced =-=[19, 14]-=-. In both cases, the constraint on the output capability of names is crucial. We believe that similar polymorphic type systems can be defined in L#. By the time the writing of this paper has been comp... |

47 |
Proofs as processes
- Abramsky
- 1994
(Show Context)
Citation Context ... delayed input replaces temporal precedencies, imposed by plain input, with causal dependencies. This appears, for instance, in Abramsky's representation of Linear Logic proofs as -calculus processes =-=[1, 6]-=-. Non-blocking message reception has been studied by Bellin and Scott [6], Boudol [10], Fu [14], Parrow and Victor [32], Yoshida [41] and van Breugel [40]. Bellin and Scott give a reduction semantics ... |

47 |
Asynchrony and the -calculus
- Boudol
- 1992
(Show Context)
Citation Context ... ab. P of the #-calculus is replaced with the simpler output particle ab, which has no continuation. The asynchronous #-calculus has been introduced by Honda and Tokoro [23], and independently Boudol =-=[9]-=-, who showed that it is expressive enough to encode the (synchronous) #-calculus. Asynchronous communications are interesting from the point of view of concurrent and distributed programming languages... |

45 | A process algebraic view of Linda coordination primitives
- Busi, Gorrieri, et al.
- 1998
(Show Context)
Citation Context ...rictions (a) and (b) do not appear. Other studies of barbed congruence, or similar contextual-based bisimulations, for mobile processes include [19, 20, 42, 14, 16] (and, for a coordination language, =-=[12]-=-). [9] studies barbed congruence in synchronous -calculus with capability types and no matching, of which (a) and (b) are a special case. Our characterisations are simpler than those in [9], but the l... |

41 |
On the π-calculus and linear logic
- Bellin, Scott
- 1994
(Show Context)
Citation Context ... delayed input replaces temporal precedencies, imposed by plain input, with causal dependencies. This appears, for instance, in Abramsky's representation of Linear Logic proofs as -calculus processes =-=[1, 6]-=-. Non-blocking message reception has been studied by Bellin and Scott [6], Boudol [10], Fu [14], Parrow and Victor [32], Yoshida [41] and van Breugel [40]. Bellin and Scott give a reduction semantics ... |

39 | On the Expressiveness of Internal Mobility in Name-Passing Calculi
- Boreale
- 1998
(Show Context)
Citation Context ...put, we derive an encoding of strong call-by-name. (iii) We prove some laws for the Joincalculus. (iv) We prove some non-full abstraction and full abstraction results for the encoding used by Boreale =-=[7]-=- to compare the expressiveness of asynchronous 1 In Milner's original theorems name a may not be exported. mobility and internal mobility (where only private names may be passed). (v) We prove that Th... |

39 | Imperative Objects and Mobile Processes
- Kleist, Sangiorgi
- 1998
(Show Context)
Citation Context ...t it cannot create a new object called a. When representing objects in the #-calculus, this usually translates into the constraint that the process receiving the object name may only use it in output =-=[64, 27, 53, 28, 45, 55, 33]-=-. Restriction (b), that is the absence of matching, is an important requirement too. Indeed, name-testing, like testing equality between pointers in imperative languages, prevents many useful program ... |

28 |
Bisimulation in NamePassing Calculi without Matching. LICS’98
- Boreale, Sangiorgi
- 1998
(Show Context)
Citation Context ...s (a) and (b) do not appear. Other studies of barbed congruence, or similar contextual-based bisimulations, for mobile processes include [19, 20, 42, 14, 16] (and, for a coordination language, [12]). =-=[9]-=- studies barbed congruence in synchronous -calculus with capability types and no matching, of which (a) and (b) are a special case. Our characterisations are simpler than those in [9], but the latter ... |

24 | Locality and non-interleaving semantics in calculi for mobile processes
- Sangiorgi
- 1994
(Show Context)
Citation Context ... links). An even more important advantage of the latter characterisation is that the number of the added links may be further reduced using bisimulation up-to context and up-to expansion techniniques =-=[36]-=- (the expansion relation is an asymmetric variant of the synchronous early bisimulation in Denition 2). For instance, under certain hypotheses on the occurrencies of b in P , the process (b)(p . b j P... |

22 | A Proof Theoretical Approach to Communication
- Fu
- 1997
(Show Context)
Citation Context |

21 |
Action calculi, or syntactic action structures
- Milner
- 1993
(Show Context)
Citation Context ...P ) (8) Laws 6 and 7 are similar to laws of restriction. Law 8 transforms a delayed input binder into a restriction binder (it might be interesting to examine delayed input from within action calculi =-=[25]-=-; for instance, law 8 is riminiscient of the denition of restriction in reAEexive action calculi [26]). 6.3. Encodings of the -calculus (In this example, we use polyadicity, which is straightforward t... |

21 | Solos in concert
- Laneve, Victor
- 1999
(Show Context)
Citation Context ...s performed by a process. Non-blocking message reception has been considered by Bellin and Scott [6], Boudol [10], Fu [20], Parrow and Victor [44], Yoshida [66] van Breugel [62] and Laneve and Victor =-=[30]-=-. Bellin and Scott give a reduction semantics for a version of #-calculus, proposed by Milner, where both message emission and message reception are non-blocking [35]; van Breugel defines a labelled 3... |

18 | Testing Theories for Asynchronous Languages
- Castellani, Hennesy
- 1998
(Show Context)
Citation Context ...input at c. An asynchronous process that non-deterministically can chose to send ab or to receive at c(x). P should be written # . ab + c(x). P (see also Castellani and Hennessy's asynchronous choice =-=[13]-=-). Nestmann and Pierce have showed that this form of choice, in which each summand is guarded by a # or by an input prefix, can be encoded in the asynchronous #-calculus [41]. L#, like several other d... |

18 |
Two bisimilarities for the -calculus
- Honda
- 1992
(Show Context)
Citation Context ...h the closure under substitutions of early bisimilarity [49, 3]. In asynchronous calculi without matching, like L#, early bisimilarity is a congruence and it coincides with its simpler ground variant =-=[22, 56]-=-, which di#ers from the early one in that there is no universal quantification in the input clause. Definition 3.3 A symmetric relation S on #-terms is an o#-bisimulation if P S Q, P --#P # ,sis not a... |

16 |
A small calculus for concurrent objects
- Honda, Tokoro
- 1991
(Show Context)
Citation Context ...here only private names may be passed). (v) We prove that Thielecke's axiomatic semantics of the Continuation Passing Style calculus [39] is operationally sound. Calculi similar to L are discussed in =-=[18, 7, 3, 41]-=-. Some of the techniques we use in Section 4 are inspired by techniques in [38]. Characterisations of barbed congruence on calculi for mobile processes include [4, 8, 3]. However, in these bisimilarit... |

13 | Minimality and separation results on asynchronous mobile processes
- Yoshida
- 1998
(Show Context)
Citation Context ...here only private names may be passed). (v) We prove that Thielecke's axiomatic semantics of the Continuation Passing Style calculus [39] is operationally sound. Calculi similar to L are discussed in =-=[18, 7, 3, 41]-=-. Some of the techniques we use in Section 4 are inspired by techniques in [38]. Characterisations of barbed congruence on calculi for mobile processes include [4, 8, 3]. However, in these bisimilarit... |

12 | Bisimulations for asynchronous mobile processes, in
- Hansen, Hiittel, et al.
- 1996
(Show Context)
Citation Context ...lso say that restriction (a) denes the location of a, and see L as a simple calculus of distributed objects. Studies of bisimulation-based behavioural equivalences for asynchronous mobile calculi are =-=[17, 19, 15, 4]-=-. In these theories, the most important algebraic law that is not in the theory of the synchronous -calculus is !a(x). ax = 0 Although this law is useful (it is used for instance by Pierce and Nestman... |

12 | Replication in concurrent combinators
- Honda, Yoshida
- 1994
(Show Context)
Citation Context ...alculus [41]. L#, like several other dialects of the #-calculus, adopts replicated inputs instead of recursion. This is because: (i) replicated input has the same expressive power as full replication =-=[25]-=- and recursion [34, 60]; (ii) replicated input has a simpler semantics and is handy for implementations. The theory and the results presented in this paper would however hold also with full replicatio... |

11 |
The name discipline of receptiveness
- Sangiorgi
(Show Context)
Citation Context ... of the Continuation Passing Style calculus [39] is operationally sound. Calculi similar to L are discussed in [18, 7, 3, 41]. Some of the techniques we use in Section 4 are inspired by techniques in =-=[38]-=-. Characterisations of barbed congruence on calculi for mobile processes include [4, 8, 3]. However, in these bisimilarity, matching transitions of processes have the same labels, therefore the proble... |

11 | Objects as mobile processes
- Huttel, Kleist
- 1996
(Show Context)
Citation Context ...t it cannot create a new object called a. When representing objects in the #-calculus, this usually translates into the constraint that the process receiving the object name may only use it in output =-=[64, 27, 53, 28, 45, 55, 33]-=-. Restriction (b), that is the absence of matching, is an important requirement too. Indeed, name-testing, like testing equality between pointers in imperative languages, prevents many useful program ... |

7 |
Action structure for the -calculus
- Milner
- 1993
(Show Context)
Citation Context ...[32], Yoshida [41] and van Breugel [40]. Bellin and Scott give a reduction semantics for a version of -calculus, proposed by Milner, where both message emission and message reception are non-blocking =-=[23]-=-; van Breugel denes a labelled transition system for such calculus and proves a correspondence with the Bellin and Scott's reduction semantics. Let DL be the calculus obtained by adding the delayed in... |