383:
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allows for hybrid approaches where the type of arguments supplied by the various calling context is known at compile time, and can generate a large number of compiled versions of the same function. Each compiled version can then be optimized for a different set of types. For instance, JIT compilation
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and has been known to be correct since 1982. It revisits the prior inferences and uses the most general type from the outset: in this case floating-point. This can however have detrimental implications, for instance using a floating-point from the outset can introduce precision issues that would have
242:
A term's type can also affect the interpretation of operations involving that term. For instance, "a song" is of composable type, so we interpret it as the thing created in the phrase "write a song". On the other hand, "a friend" is of recipient type, so we interpret it as the addressee in the phrase
882:
Frequently, however, degenerate type-inference algorithms are used that cannot backtrack and instead generate an error message in such a situation. This behavior may be preferable as type inference may not always be neutral algorithmically, as illustrated by the prior floating-point precision issue.
238:
In a typed language, a term's type determines the ways it can and cannot be used in that language. For example, consider the
English language and terms that could fill in the blank in the phrase "sing _." The term "a song" is of singable type, so it could be placed in the blank to form a meaningful
301:
from context. For example, in the phrase "I bought it for a song", we can observe that trying to give the term "a song" types like "singable" and "composable" would lead to nonsense, whereas the type "amount of currency" works out. Therefore, without having to be told, we conclude that "song" here
246:
Terms with different types can even refer to materially the same thing. For example, we would interpret "to hang up the clothes line" as putting it into use, but "to hang up the leash" as putting it away, even though, in context, both "clothes line" and "leash" might refer the same rope, just at
1301:
The algorithms used by programs like compilers are equivalent to the informally structured reasoning above, but a bit more verbose and methodical. The exact details depend on the inference algorithm chosen (see the following section for the best-known algorithm), but the example below gives the
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To obtain the information required to infer the type of an expression, the compiler either gathers this information as an aggregate and subsequent reduction of the type annotations given for its subexpressions, or through an implicit understanding of the type of various atomic values (e.g.
947:
true : Bool; 42 : Integer; 3.14159 : Real; etc.). It is through recognition of the eventual reduction of expressions to implicitly typed atomic values that the compiler for a type inferring language is able to compile a program completely without type annotations.
909:
Finally, a significant downside of complex type-inference algorithm is that the resulting type inference resolution is not going to be obvious to humans (notably because of the backtracking), which can be detrimental as code is primarily intended to be comprehensible to humans.
1916:
By design, type inference will infer the most general type appropriate. However, many languages, especially older programming languages, have slightly unsound type systems, where using a more general types may not always be algorithmically neutral. Typical cases include:
270:
The type might be provided from somewhere outside the passage. For instance, if a speaker refers to "a song" in
English, they generally do not have to tell the listener that "a song" is singable and composable; that information is part of their shared background
1059:, structuring a head element and a list tail into a bigger list or destructuring a nonempty list into its head element and its tail. It does not denote "of type" as in mathematics and elsewhere in this article; in Haskell that "of type" operator is written
942:
of a function, without explicit type annotations having been given. In many cases, it is possible to omit type annotations from a program completely if the type inference system is robust enough, or the program or language is simple enough.
1877:. If a term is well-typed in accordance with Hindley–Milner typing rules, then the rules generate a principal typing for the term. The process of discovering this principal typing is the process of "reconstruction".
1872:
The algorithm first used to perform type inference is now informally termed the
Hindley–Milner algorithm, although the algorithm should properly be attributed to Damas and Milner. It is also traditionally called
262:
arises when anything can be a set element and any predicate can define a set, but more careful typing gives several ways to resolve the paradox. In fact, Russell's paradox sparked early versions of type theory.
239:
phrase: "sing a song." On the other hand, the term "a friend" does not have the singable type, so "sing a friend" is nonsense. At best it might be metaphor; bending type rules is a feature of poetic language.
250:
Typings are often used to prevent an object from being considered too generally. For instance, if the type system treats all numbers as the same, then a programmer who accidentally writes code where
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Then we substitute until no further variables can be eliminated. The exact order is immaterial; if the code type-checks, any order will lead to the same final form. Let us begin by substituting
938:
Type inference is the ability to automatically deduce, either partially or fully, the type of an expression at compile time. The compiler is often able to infer the type of a variable or the
962:
is known to be undecidable. Furthermore, explicit type annotations can be used to optimize code by forcing the compiler to use a more specific (faster/smaller) type than it had inferred.
1921:
Floating-point types being considered as generalizations of integer types. Actually, floating-point arithmetic has different precision and wrapping issues than integers do.
243:"write a friend". In normal language, we would be surprised if "write a song" meant addressing a letter to a song or "write a friend" meant drafting a friend on paper.
958:, it is not always possible for the compiler to infer as much, and type annotations are occasionally necessary for disambiguation. For instance, type inference with
328:
In a typing, an expression E is opposed to a type T, formally written as E : T. Usually a typing only makes sense within some context, which is omitted here.
1681:α ~ β -> -> κ ζ -> -> ~ η -> θ -> λ α ~ ε -> λ -> μ ε ~ η -> ν α ~ ε -> θ -> ξ ι -> -> ~ ν -> ξ -> ο κ ~ μ ~ ο
349:
_ : T? The other way round. Given only a type, is there any expression for it or does the type have no values? Is there any example of a T? This is known as
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is supposed to mean "4 seconds" but is interpreted as "4 meters" would have no warning of their mistake until it caused problems at runtime. By incorporating
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554:
can provide more complete type inference. The ability to infer types automatically makes many programming tasks easier, leaving the programmer free to omit
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Variant/dynamic types being considered as generalizations of other types in cases where this affects the selection of operator overloads. For example, the
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to a floating point. This can be correct if the calling contexts never supply a floating point argument. Such a situation shows the difference between
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1702:α ~ β -> -> ζ -> -> ~ η -> θ -> λ α ~ ε -> λ -> ο ε ~ η -> ν α ~ ε -> θ -> ξ ι -> -> ~ ν -> ξ -> ο
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blurs the distinction between run time and compile time. However, historically, if the type of a value is known only at run-time, these languages are
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in their code, where the colon is the conventional mathematical symbol to mark a term with its type. That is, this statement is not only setting
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In the imaginary language in which the last example is written, the compiler would assume that, in the absence of information to the contrary,
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Then we make fresh type variables for subexpressions built from these terms, constraining the type of the function being invoked accordingly:
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aims to alleviate this burden, freeing the author from declaring types that the computer should be able to deduce from context.
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2447:." Proceedings of the 13th conference on Computational linguistics-Volume 3. Association for Computational Linguistics, 1990.
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for both integer and floating-point expressions. The correct type-inference algorithm for such a situation has been known
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E : T? In this case, both an expression E and a type T are given. Now, is E really a T? This scenario is known as
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Especially in programming languages, there may not be much shared background knowledge available to the computer. In
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E : _? Here, only the expression is known. If there is a way to derive a type for E, then we have accomplished
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finally proved that Milner's algorithm is complete and extended it to support systems with polymorphic references.
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It turns out that this is also the most general type, since no further constraints apply. As the inferred type of
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is an integer. In a hypothetical language supporting type inference, the code might be written like this instead:
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can be applied to functions and lists of various types, as long as the actual types match in each invocation.
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operator may add integers but may concatenate variants as strings, even if those variants hold integers.
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A version that accepts a floating-point number as input and uses floating point instructions throughout.
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POPL '82: Proceedings of the 9th ACM SIGPLAN-SIGACT symposium on principles of programming languages
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the types of all the variables at compile time. In the example above, the compiler would infer that
2473:." ACM SIGPLAN Notices. Vol. 43. No. 1. ACM, 2008." ACM SIGPLAN Notices. Vol. 43. No. 1. ACM, 2008.
2190:
792:, except that it is subject to some added constraints as described below. It would be possible to
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Constraint-based
Grammar Formalisms: Parsing and Type Inference for Natural and Computer Languages
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extended this work and proved that their algorithm always inferred the most general type. In 1978
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1969:
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here is the
Haskell list constructor, not the "of type" operator, which Haskell instead spells
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1979:
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550:(starting with version 9.0). The majority of them use a simple form of type inference; the
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The type can be declared explicitly. For example, a programmer might write a statement like
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into the type system, these mistakes can be detected much earlier. As another example,
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We also constrain the left and right sides of each equation to unify with each other:
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Damas, Luis; Milner, Robin (1982), "Principal type-schemes for functional programs",
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2485:"Machine learning theory and practice as a source of insight into universal grammar"
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on the left side of the first equation. (This pattern is known from its definition.)
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takes two integers and returns one integer. (This is how it works in, for example,
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as well as programming languages. Type inference algorithms are also used in some
589:. In most statically typed languages, the input and output types of functions and
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is a function of two arguments, so its type is constrained to be of the form
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ordinarily must be explicitly provided by type annotations. For example, in
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1788:α ~ (ζ -> ι) -> -> β -> -> ~ (ζ -> ι) -> ->
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A version that accepts an integer input and uses implicit type conversion.
906:, which forces data to a different data type, often without restrictions.
2571:
2564:
by
Michael Schwartzbach, gives an overview of Polymorphic type inference.
1237:. Nothing is special about the type variables, so it can be relabeled as
2570:
paper by Luca
Cardelli, describes algorithm, includes implementation in
451:
2319:
Hassan, Mostafa; Urban, Caterina; Eilers, Marco; Müller, Peter (2018).
519:
407: in this section. Unsourced material may be challenged and removed.
2471:
From dirt to shovels: fully automatic tool generation from ad hoc data
2379:
Milner, Robin (1978), "A Theory of Type
Polymorphism in Programming",
2327:. Lecture Notes in Computer Science. Vol. 10982. pp. 12–19.
316:
languages, this means that most types have to be declared explicitly.
1900:, independently of Hindley's work, provided an equivalent algorithm,
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The origin of this algorithm is the type inference algorithm for the
991:
applies a function to each element of a list, and may be defined as:
594:
331:
In this setting, the following questions are of particular interest:
27:
Automatic detection of the type of an expression in a formal language
890:
as a floating-point variable, and the addition implicitly converts
828:
511:
581:. In other languages, the type of an expression is known only at
1822:
eliminates all the variables specific to the second constraint:
1119:
always match lists, so the second argument must be a list type:
1056:
446:
in general. Some languages that include type inference include
2022:"Placeholder type specifiers (since C++11) - cppreference.com"
1781:, keeping the second constraint around so that we can recover
1381:
First, we make fresh type variables for each individual term:
376:
2587:
Implementation of
Hindley-Milner in Perl 5, by Nikita Borisov
2418:
Parsing and type inference for natural and computer languages
831:.) From this, the type inferencer can infer that the type of
569:, limiting the values a particular expression can take on at
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No more substitutions are possible, and relabeling gives us
886:
An algorithm of intermediate generality implicitly declares
875:
1520:, must be compatible with the type of a function taking a
820:
isn't used in a legal manner, so it wouldn't have a type.
2309:." Journal of functional programming 2.3 (1992): 245-271.
2167:"The Basics — The Swift Programming Language (Swift 5.5)"
2000:"WG14-N3007 : Type inference for object definitions"
1858:, the same as we found without going into these details.
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This is identical to how code is written in the language
771:/* this line won't work (in the proposed language) */
2354:
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must mean "little to nothing", as in the
English idiom "
1156:, corresponding with the type in the list argument, so
1762:α ~ β -> -> α ~ ε -> -> ε ~ ζ -> ι
1678:. Altogether the system of unifications to solve is:
1287:
are not inferred, but left as type variables, and so
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allows there to be at least two compiled versions of
266:
There are several ways that a term can get its type:
2558:
by Roger Hindley, explains history of type inference
2469:
Fisher, Kathleen, et al. "Fisher, Kathleen, et al. "
2287:
Bryan O'Sullivan; Don Stewart; John Goerzen (2008).
1937:
Type inference algorithms have been used to analyze
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general idea. We again begin with the definition of
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requires both of its arguments be of the same type,
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561:In some programming languages, all values have a
365:. The situation is not as comfortable when more
1743:, all possible because a type constructor like
308:", not "a piece of music, usually with lyrics".
2597:What is Hindley-Milner? (and why is it cool?)
2583:, by Andrew Forrest (retrieved July 30, 2009)
2307:Polymorphic type, region and effect inference
965:Some methods for type inference are based on
176:
8:
2483:Lappin, Shalom; Shieber, Stuart M. (2007).
2305:Talpin, Jean-Pierre, and Pierre Jouvelot. "
1912:Side-effects of using the most general type
1281:, the type of the arguments and results of
839:is an integer and thus the return value of
202:, refers to the automatic detection of the
2599:Explains Hindley–Milner, examples in Scala
2321:"MaxSMT-Based Type Inference for Python 3"
679:is a function that takes one argument, an
183:
169:
29:
2402:
2392:
1510:means "unifies with"; we are saying that
442:languages. It is often characteristic of
423:Learn how and when to remove this message
2289:"Chapter 25. Profiling and optimization"
1482:on the right side of the first equation.
1422:on the right side of the first equation.
294:'s type is an amount of time in seconds.
2381:Journal of Computer and System Sciences
2010:from the original on December 24, 2022.
1958:
1862:Hindley–Milner type inference algorithm
1414:on the left side of the first equation.
103:
60:
39:
32:
2215:"Projects/Vala/Tutorial - GNOME Wiki!"
1964:
1962:
732:/* inferred-type variable result #2 */
558:while still permitting type checking.
2458:Type-driven natural language analysis
2264:"Local Type Inference - Visual Basic"
879:not been there with an integer type.
804:have type integer since the constant
7:
2579:of Hindley–Milner type inference in
1933:Type inference for natural languages
1207:Putting the parts together leads to
855:accepts one integer as an argument.
435:Types are a feature present in some
405:adding citations to reliable sources
2436:Emele, Martin C., and Rémi Zajac. "
1664:ι -> -> ~ ν -> ξ -> ο
1558:ζ -> -> ~ η -> θ -> λ
870:, causing a conflict in the use of
720:/* inferred-type variable result */
2427:. Diss. Stanford University, 1989.
1180:means "is of type") for some type
862:is calculated by adding a decimal
25:
2593: (archived February 18, 2007)
2416:Center, Artificiał Intelligence.
2119:"Statements - The Rust Reference"
1195:, finally, is a list of whatever
858:However, in the subsequent line,
687:declares that the local variable
2191:"Documentation - Type Inference"
2071:"Inference · The Julia Language"
1815:because a type constructor like
843:is an integer. Similarly, since
808:is type integer, and hence that
444:functional programming languages
381:
324:Type-checking vs. type-inference
2095:"Kotlin language specification"
1975:Types and Programming Languages
1949:systems for natural languages.
392:needs additional citations for
1825:α ~ (ζ -> ι) -> ->
1074:function proceeds as follows.
971:satisfiability modulo theories
851:must be an integer, and thus,
373:Types in programming languages
1:
671:of this function definition,
458:(starting with version 3.0),
2394:10.1016/0022-0000(78)90014-4
1882:simply typed lambda calculus
632:/* declare integer result */
494:(starting with version 10),
359:simply typed lambda calculus
2333:10.1007/978-3-319-96142-2_2
2325:Computer Aided Verification
1791:And, finally, substituting
1506:where the "similar" symbol
1098:. In Haskell, the patterns
835:is an integer, which means
2644:
2562:Polymorphic Type Inference
2525:Stuart M. Shieber (1992).
2438:Typed unification grammars
1868:Hindley–Milner type system
1865:
1366:(Again, remember that the
1279:parametrically polymorphic
683:, and returns an integer.
552:Hindley–Milner type system
361:, all three questions are
2504:10.1017/s0022226707004628
1641:shall denote the type of
1619:shall denote the type of
1600:shall denote the type of
1566:shall denote the type of
1538:shall denote the type of
1493:shall denote the type of
1476:shall denote the type of
1464:shall denote the type of
1452:shall denote the type of
1440:shall denote the type of
1428:shall denote the type of
1419:shall denote the type of
1411:shall denote the type of
1400:shall denote the type of
1388:shall denote the type of
898:, which does not involve
868:floating-point arithmetic
290:part also indicates that
1947:constraint-based grammar
1310:
1239:
993:
952:higher-order programming
915:just-in-time compilation
913:The recent emergence of
904:implicit type conversion
693:
599:
575:just-in-time compilation
276:delay: seconds := 4
234:Nontechnical explanation
2556:Archived e-mail message
2368:, ACM, pp. 207–212
1434:in the second equation.
1150:, which must have type
967:constraint satisfaction
565:explicitly declared at
2492:Journal of Linguistics
2239:"The Dart type system"
2195:www.typescriptlang.org
1406:in the first equation.
1394:that we want to infer.
1186:. The return value of
1068:Type inference on the
585:; these languages are
303:
206:of an expression in a
53:Strong vs. weak typing
2047:"Type Inference - F#"
1633:α ~ ε -> θ -> ξ
1592:α ~ ε -> λ -> μ
1134:. Its first argument
960:polymorphic recursion
934:Technical description
212:programming languages
1884:that was devised by
1504:α ~ β -> -> κ
950:In complex forms of
401:improve this article
222:in some branches of
2147:Scala Documentation
2026:en.cppreference.com
1875:type reconstruction
1662:. We conclude that
1631:. We conclude that
1609:. We conclude that
1590:. We conclude that
1556:. We conclude that
1502:. We conclude that
1055:in Haskell denotes
981:As an example, the
369:types are allowed.
200:type reconstruction
198:, sometimes called
2568:Basic Typechecking
2443:2018-02-05 at the
2423:2012-07-04 at the
2293:Real World Haskell
2268:docs.microsoft.com
2075:docs.julialang.org
2051:docs.microsoft.com
1970:Benjamin C. Pierce
1759:in its arguments:
1528:s and returning a
977:High-Level Example
673:int add_one(int x)
2538:978-0-262-19324-5
2456:Pareschi, Remo. "
2342:978-3-319-96141-5
2262:KathleenDollard.
2123:doc.rust-lang.org
1985:978-0-262-16209-8
1943:grammar induction
1939:natural languages
1892:in 1958. In 1969
579:dynamically typed
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260:Russell's paradox
247:different times.
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573:. Increasingly,
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440:statically typed
428:
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314:manifestly typed
297:The type can be
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210:. These include
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104:Minor categories
61:Major categories
40:General concepts
30:
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900:type conversion
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817:
816:. The variable
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591:local variables
429:
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375:
326:
291:
287:
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279:
275:
251:
236:
208:formal language
189:
28:
23:
22:
18:Inferred typing
15:
12:
11:
5:
2641:
2639:
2631:
2630:
2625:
2620:
2615:
2613:Type inference
2605:
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2600:
2594:
2584:
2577:Implementation
2574:
2565:
2559:
2551:
2550:External links
2548:
2545:
2544:
2537:
2517:
2498:(2): 393–427.
2475:
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2409:
2387:(3): 348–375,
2371:
2348:
2341:
2311:
2298:
2279:
2254:
2230:
2219:wiki.gnome.org
2206:
2182:
2171:docs.swift.org
2158:
2134:
2110:
2099:kotlinlang.org
2086:
2062:
2037:
2013:
2006:. 2022-06-10.
1991:
1984:
1957:
1956:
1954:
1951:
1934:
1931:
1930:
1929:
1922:
1913:
1910:
1866:Main article:
1863:
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1824:
1787:
1761:
1701:
1680:
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1667:
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1614:
1595:
1561:
1533:
1524:and a list of
1514:, the type of
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1471:
1459:
1447:
1435:
1423:
1415:
1407:
1395:
1311:
1298:
1295:
1240:
1128:for some type
994:
978:
975:
940:type signature
935:
932:
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927:
896:type inference
812:is a function
694:
600:
431:
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389:
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344:type inference
340:
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318:Type inference
310:
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288:delay: seconds
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196:Type inference
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2549:
2540:
2534:
2531:. MIT Press.
2530:
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2017:
2014:
2009:
2005:
2001:
1995:
1992:
1987:
1981:
1978:. MIT Press.
1977:
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1971:
1965:
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1959:
1952:
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1923:
1920:
1919:
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1886:Haskell Curry
1883:
1878:
1876:
1869:
1861:
1859:
1823:
1821:
1786:
1765:Substituting
1760:
1758:
1705:Substituting
1700:
1679:
1637:
1615:
1611:ε ~ η -> ν
1596:
1562:
1534:
1489:
1488:
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1416:
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1309:
1296:
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1201:produces, so
1143:
1066:
1058:
1049:(Recall that
992:
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830:
821:
814:int -> int
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438:
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424:
416:
413:November 2020
406:
402:
396:
395:
390:This section
388:
384:
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372:
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368:
364:
360:
352:
348:
345:
341:
338:
337:type-checking
334:
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321:
319:
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307:
306:
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296:
282:to the value
273:
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164:
163:
158:
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153:
150:
148:
147:Substructural
145:
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138:
135:
133:
130:
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51:
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46:
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44:
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38:
35:
31:
19:
2618:Type systems
2527:
2520:
2495:
2491:
2478:
2465:
2452:
2432:
2412:
2384:
2380:
2374:
2361:
2324:
2314:
2301:
2292:
2282:
2271:. Retrieved
2267:
2257:
2246:. Retrieved
2242:
2233:
2222:. Retrieved
2218:
2209:
2198:. Retrieved
2194:
2185:
2174:. Retrieved
2170:
2161:
2150:. Retrieved
2146:
2137:
2126:. Retrieved
2122:
2113:
2102:. Retrieved
2098:
2089:
2078:. Retrieved
2074:
2065:
2054:. Retrieved
2050:
2040:
2029:. Retrieved
2025:
2016:
2004:open-std.org
2003:
1994:
1974:
1936:
1915:
1898:Robin Milner
1879:
1874:
1871:
1827:
1790:
1785:at the end:
1764:
1704:
1683:
1669:
1485:
1380:
1365:
1300:
1270:
1206:
1067:
1048:
980:
964:
956:polymorphism
949:
945:
937:
919:
912:
908:
895:
887:
885:
881:
859:
857:
822:
793:
787:
666:
583:compile time
567:compile time
560:
548:Visual Basic
434:
419:
410:
399:Please help
394:verification
391:
356:
343:
330:
327:
317:
311:
298:
265:
249:
245:
241:
237:
216:type systems
199:
195:
194:
132:Intersection
81:
34:Type systems
2623:Type theory
2295:. O'Reilly.
1902:Algorithm W
1890:Robert Feys
1799:as well as
1793:(ζ -> ι)
685:int result;
228:linguistics
218:, but also
96:Duck typing
48:Type safety
2607:Categories
2460:." (1988).
2273:2021-06-28
2248:2020-11-21
2224:2021-06-28
2200:2020-11-21
2176:2021-06-28
2152:2020-11-21
2128:2021-06-28
2104:2021-06-28
2080:2020-11-21
2056:2020-11-21
2045:cartermp.
2031:2021-08-15
1953:References
1906:Luis Damas
1904:. In 1982
1820:invertible
1757:invertible
1065:instead.)
876:since 1958
536:TypeScript
367:expressive
305:for a song
286:, but the
271:knowledge.
142:Refinement
91:structural
2628:Inference
2512:215762538
1767:ζ -> ι
985:function
669:signature
563:data type
480:FreeBASIC
363:decidable
117:Dependent
2572:Modula-2
2441:Archived
2421:Archived
2243:dart.dev
2008:Archived
1972:(2002).
571:run-time
437:strongly
357:For the
299:inferred
112:Abstract
82:inferred
78:Manifest
2589:at the
1142:applied
983:Haskell
920:add_one
888:result2
860:result2
853:add_one
841:add_one
818:result2
810:add_one
753:result2
726:result2
696:add_one
681:integer
677:add_one
605:add_one
520:RPython
488:Haskell
468:Crystal
157:Session
127:Gradual
87:Nominal
73:dynamic
2535:
2510:
2339:
1982:
1732:, and
902:, and
837:result
798:result
777:result
774:return
735:result
714:result
689:result
656:result
653:return
635:result
626:result
595:ANSI C
546:, and
518:, Q#,
500:Kotlin
460:Chapel
152:Unique
137:Latent
69:Static
2581:Scala
2508:S2CID
2488:(PDF)
2366:(PDF)
1855:->
1852:->
1843:->
1749:->
1676:μ ~ ο
1647:first
1606:first
1578:first
1544:first
1455:first
1349:first
1331:first
1266:->
1263:->
1254:->
1234:->
1231:->
1222:->
1168:->
1147:first
1107:first
1092:->
1086:->
1032:first
1014:first
866:with
833:x + 1
829:OCaml
794:infer
532:Swift
528:Scala
512:OCaml
496:Julia
464:Clean
452:C++11
292:delay
280:delay
256:units
2533:ISBN
2337:ISBN
1980:ISBN
1945:and
1888:and
1811:for
1807:and
1803:for
1795:for
1777:for
1773:and
1769:for
1739:and
1735:for
1728:for
1720:and
1716:for
1709:for
1695:for
1692:and
1688:for
1674:and
1672:κ ~
1659:rest
1628:rest
1584:rest
1550:rest
1467:rest
1361:rest
1337:rest
1113:rest
1101:and
1057:cons
1044:rest
1020:rest
954:and
800:and
790:Dart
667:The
544:Dart
540:Vala
524:Rust
492:Java
226:and
204:type
89:vs.
80:vs.
71:vs.
2500:doi
2399:hdl
2389:doi
2329:doi
1831:map
1818:is
1755:is
1653:map
1622:map
1569:map
1517:map
1496:map
1391:map
1378:.)
1355:map
1322:map
1313:map
1305:map
1290:map
1277:is
1274:map
1242:map
1210:map
1189:map
1140:is
1077:map
1071:map
1038:map
1005:map
996:map
988:map
969:or
864:1.0
765:1.0
723:var
711:var
623:int
611:int
602:int
516:Opa
508:Nim
448:C23
403:by
2609::
2506:.
2496:43
2494:.
2490:.
2397:,
2385:17
2383:,
2351:^
2335:.
2323:.
2291:.
2266:.
2241:.
2217:.
2193:.
2169:.
2145:.
2121:.
2097:.
2073:.
2049:.
2024:.
2002:.
1961:^
1834:::
1724:,
1713:,
1699::
1375:::
1308::
1245:::
1213:::
1204:.
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