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Add a new smart combinator boa-preserving and document the rest of the smart combinators. Simpler implementation of nullary.

db4
Doug Coleman 2010-06-23 14:54:00 -05:00
parent 7599841221
commit 1806a0ce77
2 changed files with 173 additions and 14 deletions
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178
basis/combinators/smart/smart-docs.factor
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@ -1,7 +1,7 @@
! Copyright (C) 2009 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: help.markup help.syntax kernel quotations math sequences
stack-checker ;
USING: classes.tuple help.markup help.syntax kernel math
quotations sequences stack-checker ;
IN: combinators.smart
HELP: input<sequence
@ -116,22 +116,168 @@ HELP: keep-inputs
{ drop-outputs keep-inputs } related-words
HELP: boa-preserving
{ $values
{ "tuple-class" tuple-class }
{ "quot" quotation }
}
{ $description "Constructs a tuple using a boa construtor and keeps the objects on the stack. The tuple will be at the top of the stack." }
{ $examples
{ $example
"""USING: colors combinators.smart kernel prettyprint ;
IN: combinators.smart.tests
TUPLE: painting title artist ;
"L'Origine du monde" "Courbet" painting boa-preserving [ . ] tri@ """
""""L'Origine du monde"
"Courbet"
T{ painting
{ title "L'Origine du monde" }
{ artist "Courbet" }
}"""
}
} ;
HELP: dropping
{ $values
{ "quot" quotation }
{ "quot" quotation }
}
{ $description "Outputs a quotation that, when called, will have the effect of dropping the number of inputs to the original quotation." }
{ $examples
{ $example
"""USING: combinators.smart math prettyprint ;
[ + + ] dropping ."""
"""[ 3 ndrop ]"""
}
} ;
HELP: input<sequence-unsafe
{ $values
{ "quot" quotation }
{ "quot" quotation }
}
{ $description "An unsafe version of " { $link input<sequence-unsafe } "." } ;
HELP: map-reduce-outputs
{ $values
{ "quot" quotation } { "mapper" quotation } { "reducer" quotation }
{ "quot" quotation }
}
{ $description "Infers the number of outputs from " { $snippet "quot" } " and, treating those outputs as a sequence, calls " { $link map-reduce } " on them." }
{ $examples
{ $example
"""USING: math combinators.smart prettyprint ;
[ 1 2 3 ] [ sq ] [ + ] map-reduce-outputs ."""
"14"
}
} ;
HELP: nullary
{ $values
{ "quot" quotation }
{ "quot" quotation }
}
{ $description "Infers the number of inputs to a quotation and drops them from the stack." }
{ $examples
{ $example
"""USING: combinators.smart kernel math ;
1 2 [ + ] nullary"""
""
}
} ;
HELP: preserving
{ $values
{ "quot" quotation }
{ "quot" quotation }
}
{ $description "Calls a quotation and leaves any consumed inputs on the stack beneath the quotation's outputs." }
{ $examples
{ $example
"""USING: combinators.smart kernel math prettyprint ;
1 2 [ + ] preserving [ . ] tri@"""
"""1
2
3"""
}
} ;
HELP: smart-apply
{ $values
{ "quot" quotation } { "n" integer }
{ "quot" quotation }
}
{ $description "Applies a quotation to the datastack " { $snippet "n" } " times, starting lower on the stack and working up in increments of the number of inferred inputs to the quotation." }
{ $examples
{ $example
"""USING: combinators.smart prettyprint math kernel ;
1 2 3 4 [ + ] 2 smart-apply [ . ] bi@"""
"""3
7"""
}
} ;
HELP: smart-if
{ $values
{ "pred" quotation } { "true" quotation } { "false" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link if } " that takes three quotations, where the first quotation is a predicate that preserves any inputs it consumes." } ;
HELP: smart-if*
{ $values
{ "pred" quotation } { "true" quotation } { "false" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link if } " that takes three quotations, where the first quotation is a predicate that preserves any inputs it consumes, the second is the " { $snippet "true" } " branch, and the third is the " { $snippet "false" } " branch. If the " { $snippet "true" } " branch is taken, the values are left on the stack and the quotation is called. If the " { $snippet "false" } " branch is taken, the number of inputs inferred from predicate quotation is dropped and the quotation is called." } ;
HELP: smart-unless
{ $values
{ "pred" quotation } { "false" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link unless } " that takes two quotations, where the first quotation is a predicate that preserves any inputs it consumes and the second is the " { $snippet "false" } " branch." } ;
HELP: smart-unless*
{ $values
{ "pred" quotation } { "false" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link unless } " that takes two quotations, where the first quotation is a predicate that preserves any inputs it consumes and the second is the " { $snippet "false" } " branch. If the " { $snippet "true" } " branch is taken, the values are left on the stack. If the " { $snippet "false" } " branch is taken, the number of inputs inferred from predicate quotation is dropped and the quotation is called." } ;
HELP: smart-when
{ $values
{ "pred" quotation } { "true" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link when } " that takes two quotations, where the first quotation is a predicate that preserves any inputs it consumes and the second is the " { $snippet "true" } " branch." } ;
HELP: smart-when*
{ $values
{ "pred" quotation } { "true" quotation }
{ "quot" quotation }
}
{ $description "A version of " { $link when } " that takes two quotations, where the first quotation is a predicate that preserves any inputs it consumes and the second is the " { $snippet "true" } " branch. If the " { $snippet "true" } " branch is taken, the values are left on the stack and the quotation is called. If the " { $snippet "false" } " branch is taken, the number of inputs inferred from predicate quotation is dropped." } ;
ARTICLE: "combinators.smart" "Smart combinators"
"A " { $emphasis "smart combinator" } " is a macro which reflects on the stack effect of an input quotation. The " { $vocab-link "combinators.smart" } " vocabulary implements a few simple smart combinators which look at the static stack effects of input quotations and generate code which produces or consumes the relevant number of stack values." $nl
"Call a quotation and discard all output values or preserve all input values:"
{ $subsections
drop-outputs
keep-inputs
}
"Take all input values from a sequence:"
{ $subsections input<sequence }
{ $subsections
input<sequence
input<sequence-unsafe
}
"Store all output values to a sequence:"
{ $subsections
output>sequence
output>array
}
"Reducing the set of output values:"
{ $subsections reduce-outputs }
{ $subsections
reduce-outputs
map-reduce-outputs
}
"Applying a quotation to groups of elements on the stack:"
{ $subsections smart-apply }
"Summing output values:"
{ $subsections sum-outputs }
"Concatenating output values:"
@ -139,6 +285,20 @@ ARTICLE: "combinators.smart" "Smart combinators"
append-outputs
append-outputs-as
}
"Constructing tuples:"
{ $subsections
boa-preserving
}
"Drop the outputs after calling a quotation:"
{ $subsections drop-outputs }
"Cause a quotation to act as a no-op and drop the inputs:"
{ $subsection nullary }
"Preserve the inputs below or above the outputs of the quotation:"
{ $subsections preserving keep-inputs }
"Versions of if that infer how many inputs to keep from the predicate quotation:"
{ $subsections smart-if smart-when smart-unless }
"Versions of if* that infer how many inputs to keep from the predicate quotation:"
{ $subsections smart-if* smart-when* smart-unless* }
"New smart combinators can be created by defining " { $link "macros" } " which call " { $link infer } "." ;
ABOUT: "combinators.smart"

9
basis/combinators/smart/smart.factor
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@ -46,14 +46,13 @@ MACRO: append-outputs ( quot -- seq )
MACRO: preserving ( quot -- )
[ inputs ] keep '[ _ ndup @ ] ;
MACRO: nullary ( quot -- quot' )
dup outputs '[ @ _ ndrop ] ;
MACRO: boa-preserving ( tuple-class -- )
'[ [ _ boa ] preserving ] ;
MACRO: dropping ( quot -- quot' )
inputs '[ [ _ ndrop ] ] ;
MACRO: balancing ( quot -- quot' )
'[ _ [ preserving ] [ dropping ] bi ] ;
MACRO: nullary ( quot -- quot' ) dropping ;
MACRO: smart-if ( pred true false -- quot )
'[ _ preserving _ _ if ] ;
@ -65,7 +64,7 @@ MACRO: smart-unless ( pred false -- quot )
'[ _ [ ] _ smart-if ] ;
MACRO: smart-if* ( pred true false -- quot )
'[ _ balancing _ swap _ compose if ] ;
'[ _ [ preserving ] [ dropping ] bi _ swap _ compose if ] ;
MACRO: smart-when* ( pred true -- quot )
'[ _ _ [ ] smart-if* ] ;