make hash-lang delayed so that scribble/manual doesn't directly depend on scribblings/guide

svn: r8260

collects/scribble/manual.ss

@@ -49,7 +49,7 @@
                               #'here
                               `(unsyntax (make-element
                                           #f
-                                          (list hash-lang
+                                          (list (hash-lang)
                                                 (hspace 1)
                                                 (as-modname-link
                                                  ',#'lang
@@ -140,7 +140,7 @@
                 (list (make-paragraph
                        (if lang?
                            (list (hspace 1)
-                                 hash-lang
+                                 (hash-lang)
                                  (hspace 1)
                                  (make-defschememodname name))
                            (list
@@ -1794,12 +1794,12 @@
              c)))
   (provide pidefterm)
 
-
-  (define hash-lang (make-link-element
-                     "schememodlink"
-                     (list (schememodfont "#lang"))
-                     `(part ,(doc-prefix '(lib "scribblings/guide/guide.scrbl")
-                                         "hash-lang"))))
+  (provide hash-lang)
+  (define (hash-lang) (make-link-element
+                       "schememodlink"
+                       (list (schememodfont "#lang"))
+                       `(part ,(doc-prefix '(lib "scribblings/guide/guide.scrbl")
+                                           "hash-lang"))))
   
   ;; ----------------------------------------
 

collects/scribblings/guide/welcome.scrbl

@@ -54,12 +54,12 @@ work in the normal variant of Scheme (as opposed to the smaller
 @schememodname[scheme/base], or many other possibilities).
 
 If you've used DrScheme before with something other than a program
-that starts @schemefont{#lang}, DrScheme will remember the last language
-that you used, instead of inferring the language from the
-@schemefont{#lang} line. In that case, use the @menuitem["Language"
-"Choose Language..."]  menu item.  In the the dialog that appears,
-select the first item, which is @onscreen{Module}. Put the
-@schemefont{#lang} line above in the top text area, still.
+that starts @hash-lang[], DrScheme will remember the last language
+that you used, instead of inferring the language from the @hash-lang[]
+line. In that case, use the @menuitem["Language" "Choose Language..."]
+menu item.  In the the dialog that appears, select the first item,
+which is @onscreen{Module}. Put the @hash-lang[] line above in the top
+text area, still.
 
 @; ----------------------------------------------------------------------
 @section{Interacting with Scheme}
@@ -106,7 +106,7 @@ Although you can evaluate the @scheme[define] form in the @tech{REPL},
 definitions are normally a part of a program that you want to keep and
 use later. So, in DrScheme, you'd normally put the definition in the
 top text area---called the @defterm{definitions area}---along with the
-@schemefont{#lang} prefix:
+@hash-lang[] prefix:
 
 @schememod[
 scheme
@@ -163,10 +163,9 @@ traditional Scheme environment, but we strongly recommend against using
 
 Writing definitions outside of a module leads to bad error messages,
 bad performance, and awkward scripting to combine and run
-programs. The problems are not specific to @exec{mzscheme};
-they're fundamental limitations of the traditional top-level
-environment, which Scheme and Lisp implementations have historically
-fought with ad hoc command-line flags, compiler directives, and
-build tools. The module system is to designed to avoid the problems,
-so start with @schemefont{#lang}, and you'll be happier with
-PLT Scheme in the long run.
+programs. The problems are not specific to @exec{mzscheme}; they're
+fundamental limitations of the traditional top-level environment,
+which Scheme and Lisp implementations have historically fought with ad
+hoc command-line flags, compiler directives, and build tools. The
+module system is to designed to avoid the problems, so start with
+@hash-lang[], and you'll be happier with PLT Scheme in the long run.

collects/scribblings/scribble/manual.scrbl

@@ -821,6 +821,9 @@ Returns @scheme[#t] if @scheme[v] is a bibliography entry created by
 @defthing[PLaneT string?]{@scheme["PLaneT"] (to help make sure you get
 the letters in the right case).}
 
+@defproc[(hash-lang) element?]{Returns an element for @hash-lang[]
+that is hyperlinked to an explanation.}
+
 @defthing[void-const element?]{Returns an element for @|void-const|.}
 
 @defthing[undefined-const element?]{Returns an element for @|undefined-const|.}