| slovo | definícia |
iswim
(foldoc) | ISWIM
(If You See What I Mean) An influential but
unimplemented computer programming language described in the
article by Peter J. Landin cited below. Landin attempted to
capture all known programming language concepts, including
assignment and control operators such as goto and
coroutines, within a single lambda calculus based
framework.
ISWIM is an imperative language with a functional core,
consisting of sugared lambda calculus plus {mutable
variables} and assignment. A powerful control mechanism,
Landin's J operator, enables capture of the current
continuation (the call/cc operator of Scheme is a
simplified version). Being based on lambda calculus ISWIM had
higher order functions and lexically scoped variables.
The operational semantics of ISWIM are defined using
Landin's SECD machine and use call-by-value ({eager
evaluation}). To make ISWIM look more like mathematical
notation, Landin replaced ALGOL's semicolons and begin end
blocks with the off-side rule and scoping based on
indentation.
An ISWIM program is a single expression qualified by "where"
clauses (auxiliary definitions including equations among
variables), conditional expressions and function definitions.
With CPL, ISWIM was one of the first programming languages
to use "where" clauses.
New data types could be defined as a (possibly recursive)
sum of products like the algebraic data types found in
modern functional languages. ISWIM variables were probably
dynamically typed but Landin may have planned some form of
type inference.
Concepts from ISWIM appear in Art Evan's PAL and John
Reynold's Gedanken, Milner's ML and purely functional
languages with lazy evaluation like SASL, Miranda and
Haskell.
[{"The Next 700 Programming Languages"
(http://www.cs.utah.edu/~wilson/compilers/old/papers/p157-landin.pdf)},
P.J. Landin, CACM 9(3):157-166, Mar 1966].
(2007-03-20)
|
| | podobné slovo | definícia |
iswim
(foldoc) | ISWIM
(If You See What I Mean) An influential but
unimplemented computer programming language described in the
article by Peter J. Landin cited below. Landin attempted to
capture all known programming language concepts, including
assignment and control operators such as goto and
coroutines, within a single lambda calculus based
framework.
ISWIM is an imperative language with a functional core,
consisting of sugared lambda calculus plus {mutable
variables} and assignment. A powerful control mechanism,
Landin's J operator, enables capture of the current
continuation (the call/cc operator of Scheme is a
simplified version). Being based on lambda calculus ISWIM had
higher order functions and lexically scoped variables.
The operational semantics of ISWIM are defined using
Landin's SECD machine and use call-by-value ({eager
evaluation}). To make ISWIM look more like mathematical
notation, Landin replaced ALGOL's semicolons and begin end
blocks with the off-side rule and scoping based on
indentation.
An ISWIM program is a single expression qualified by "where"
clauses (auxiliary definitions including equations among
variables), conditional expressions and function definitions.
With CPL, ISWIM was one of the first programming languages
to use "where" clauses.
New data types could be defined as a (possibly recursive)
sum of products like the algebraic data types found in
modern functional languages. ISWIM variables were probably
dynamically typed but Landin may have planned some form of
type inference.
Concepts from ISWIM appear in Art Evan's PAL and John
Reynold's Gedanken, Milner's ML and purely functional
languages with lazy evaluation like SASL, Miranda and
Haskell.
[{"The Next 700 Programming Languages"
(http://www.cs.utah.edu/~wilson/compilers/old/papers/p157-landin.pdf)},
P.J. Landin, CACM 9(3):157-166, Mar 1966].
(2007-03-20)
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