! 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
{ 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:"
+"Take all input values from a sequence:"
{ $subsections
- drop-outputs
- keep-inputs
+ input<sequence
+ input<sequence-unsafe
}
-"Take all input values from a sequence:"
-{ $subsections input<sequence }
"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:"
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"
projects / factor.git / commitdiff