minor tweaks, add missing file

doc/handbook/handbook.facts

@@ -1,23 +1,13 @@
 USING: help parser prettyprint ;
 
 ARTICLE: "handbook" "Factor documentation"
-"Welcome to Factor! Factor documentation is takes the form of an outline, with cross-referencing hyperlinks between topics. You can click the triangle next to a topic heading to expand the topic:"
+"Welcome to Factor! Factor documentation is takes the form of an outline, with cross-referencing hyperlinks between topics. You can click the triangle next to a topic heading to expand the topic."
+$terpri
+"There is some introductory material you will find useful when starting out:"
 { $subsection "presentation-intro" }
-"There is a short language tutorial:"
 { $subsection "tutorial" }
-"Some words for performing common operations at the listener:"
+{ $subsection "quickref" }
-{ $list
+"More detailed reference documentation:"
-    {
-        "You can read the documentation for a word with " { $link help } ":"
-        { $code "\\ reverse help" }
-    }
-    { "You can print the top of the stack with " { $link . } }
-    {
-        "Source files are loaded with " { $link run-file } ":"
-        { $code "\"tetris.factor\" run-file" }
-    }
-}
-"Detailed documentation:"
 { $subsection "syntax" }
 { $subsection "dataflow" }
 { $subsection "words" }
@@ -32,3 +22,24 @@ $terpri
 "When you place the mouse over a presentation, it is highlighted with a surrounding border."
 $terpri
 "Clicking a presentation with the left mouse button invokes a default command. Clicking the right mouse button displays a menu of applicable commands." ;
+
+ARTICLE: "quickref" "Quick reference"
+"Some words for performing common operations at the listener:"
+{ $list
+    {
+        "You can read the documentation for a word with " { $link help } ":"
+        { $code "\\ reverse help" }
+    }
+    { "You can print the top of the stack with " { $link . } }
+    {
+        "Source files are loaded with " { $link run-file } ":"
+        { $code "\"tetris.factor\" run-file" }
+    }
+}
+"If you enter an invalid word name, you will get a \"not a number\" error:"
+{ $example
+    "fdafasfa"
+    "An unhandled error was caught:\n\nParsing <interactive>:1\nfdafasfa\n        ^\n\"Not a number\"\n\n:s :r show stacks at time of error.\n:get ( var -- value ) inspects the error namestack."
+}
+"Sometimes, the word " { $emphasis "does" } " exist, but you might need to " { $link POSTPONE: USE: } " its vocabulary first. The " { $link apropos } " word can help locate the correct vocabulary:"
+{ $example "\"<label>\" apropos" "IN: gadgets-labels : <label>\nIN: compiler-backend : <label>" } ;

library/help/markup.factor

@@ -27,7 +27,9 @@ PREDICATE: array simple-element
     ] if ;
 
 M: string print-element
-    " " split [ write-term ] [ bl ] interleave ;
+    " " split
+    [ dup empty? [ drop ] [ write-term ] if ]
+    [ bl ] interleave ;
 
 M: array print-element
     unswons* execute ;

library/math/constants.facts

@@ -0,0 +1,39 @@
+USING: help kernel-internals math ;
+
+HELP: cells "( m -- n )"
+{ $values { "m" "an integer" } { "n" "an integer" } }
+{ $description "Computes the number of bytes corresponding to " { $snippet "m" } " CPU operand-sized cells." } ;
+
+HELP: cell-bits "( m -- n )"
+{ $values { "m" "an integer" } { "n" "an integer" } }
+{ $description "Computes the number of bits corresponding to " { $snippet "m" } " CPU operand-sized cells." } ;
+
+HELP: i "( -- i )"
+{ $values { "i" "the imaginary unit" } } ;
+
+HELP: -i "( -- -i )"
+{ $values { "i" "the negated imaginary unit" } } ;
+
+HELP: inf "( -- inf )"
+{ $values { "inf" "floating point positive infinity" } } ;
+
+HELP: -inf "( -- -inf )"
+{ $values { "-inf" "floating point negative infinity" } } ;
+
+HELP: e "( -- e )"
+{ $values { "e" "base of natural logarithm" } } ;
+
+HELP: pi "( -- pi )"
+{ $values { "pi" "circumference of circle with diameter 1" } } ;
+
+HELP: epsilon "( -- epsilon )"
+{ $values { "epsilon" "smallest floating point value you can add to 1 without underflow" } } ;
+
+HELP: first-bignum "( -- n )"
+{ $values { "n" "smallest positive integer not representable by a fixnum" } } ;
+
+HELP: most-positive-fixnum "( -- n )"
+{ $values { "n" "largest positive integer representable by a fixnum" } } ;
+
+HELP: most-negative-fixnum "( -- n )"
+{ $values { "n" "smallest negative integer representable by a fixnum" } } ;

library/ui/presentations.factor

@@ -40,13 +40,14 @@ M: gadget-stream stream-write1 ( char stream -- )
     presented [ <command-button> ] apply-style ;
 
 : apply-break-style ( style gadget -- style gadget )
-    word-break [ <word-break-gadget> ] apply-style ;
+    word-break [ drop <word-break-gadget> ] apply-style ;
 
 : <presentation> ( style text -- gadget )
     <label>
     apply-foreground-style
     apply-background-style
     apply-font-style
+    apply-break-style
     apply-command-style
     nip ;