Move display & MIME stuff out of helpDB, xrefs (JuliaLang#22890)

base/docs/helpdb/Base.jl

@@ -391,21 +391,6 @@ Like [`randsubseq`](@ref), but the results are stored in `S`
 """
 randsubseq!
 
-"""
- redisplay(x)
- redisplay(d::Display, x)
- redisplay(mime, x)
- redisplay(d::Display, mime, x)
-
-By default, the `redisplay` functions simply call [`display`](@ref).
-However, some display backends may override `redisplay` to modify an existing
-display of `x` (if any).
-Using `redisplay` is also a hint to the backend that `x` may be redisplayed
-several times, and the backend may choose to defer the display until
-(for example) the next interactive prompt.
-"""
-redisplay
-
 """
  /(x, y)
 
@@ -421,26 +406,6 @@ Show every part of the representation of a value.
 """
 dump
 
-"""
- display(x)
- display(d::Display, x)
- display(mime, x)
- display(d::Display, mime, x)
-
-Display `x` using the topmost applicable display in the display stack, typically using the
-richest supported multimedia output for `x`, with plain-text [`STDOUT`](@ref) output as a fallback.
-The `display(d, x)` variant attempts to display `x` on the given display `d` only, throwing
-a `MethodError` if `d` cannot display objects of this type.
-
-There are also two variants with a `mime` argument (a MIME type string, such as
-`"image/png"`), which attempt to display `x` using the requested MIME type *only*, throwing
-a `MethodError` if this type is not supported by either the display(s) or by `x`. With these
-variants, one can also supply the "raw" data in the requested MIME type by passing
-`x::AbstractString` (for MIME types with text-based storage, such as text/html or
-application/postscript) or `x::Vector{UInt8}` (for binary MIME types).
-"""
-display
-
 """
  tuple(xs...)
 
@@ -865,15 +830,6 @@ Seek a stream to the given position.
 """
 seek
 
-"""
- popdisplay()
- popdisplay(d::Display)
-
-Pop the topmost backend off of the display-backend stack, or the topmost copy of `d` in the
-second variant.
-"""
-popdisplay
-
 """
  cglobal((symbol, library) [, type=Void])
 
@@ -1397,15 +1353,6 @@ In this example, `b` is a runnable `Task` that hasn't started yet.
 """
 Task
 
-"""
- pushdisplay(d::Display)
-
-Pushes a new display `d` on top of the global display-backend stack. Calling `display(x)` or
-`display(mime, x)` will display `x` on the topmost compatible backend in the stack (i.e.,
-the topmost backend that does not throw a `MethodError`).
-"""
-pushdisplay
-
 """
  StackOverflowError()
 
@@ -1448,7 +1395,7 @@ nfields
 """
  show(stream, mime, x)
 
-The `display` functions ultimately call `show` in order to write an object `x` as a
+The [`display`](@ref) functions ultimately call `show` in order to write an object `x` as a
 given `mime` type to a given I/O `stream` (usually a memory buffer), if possible. In order
 to provide a rich multimedia representation of a user-defined type `T`, it is only necessary
 to define a new `show` method for `T`, via: `show(stream, ::MIME"mime", x::T) = ...`,

base/multimedia.jl

@@ -185,10 +185,26 @@ close(d::TextDisplay) = close(d.io)
 # Display that is capable of displaying x (doesn't throw an error)
 
 const displays = Display[]
+
+"""
+ pushdisplay(d::Display)
+
+Pushes a new display `d` on top of the global display-backend stack. Calling `display(x)` or
+`display(mime, x)` will display `x` on the topmost compatible backend in the stack (i.e.,
+the topmost backend that does not throw a [`MethodError`](@ref)).
+"""
 function pushdisplay(d::Display)
  global displays
  push!(displays, d)
 end
+
+"""
+ popdisplay()
+ popdisplay(d::Display)
+
+Pop the topmost backend off of the display-backend stack, or the topmost copy of `d` in the
+second variant.
+"""
 popdisplay() = pop!(displays)
 function popdisplay(d::Display)
  for i = length(displays):-1:1
@@ -205,6 +221,24 @@ end
 
 xdisplayable(D::Display, args...) = applicable(display, D, args...)
 
+"""
+ display(x)
+ display(d::Display, x)
+ display(mime, x)
+ display(d::Display, mime, x)
+
+Display `x` using the topmost applicable display in the display stack, typically using the
+richest supported multimedia output for `x`, with plain-text [`STDOUT`](@ref) output as a fallback.
+The `display(d, x)` variant attempts to display `x` on the given display `d` only, throwing
+a [`MethodError`](@ref) if `d` cannot display objects of this type.
+
+There are also two variants with a `mime` argument (a MIME type string, such as
+`"image/png"`), which attempt to display `x` using the requested MIME type *only*, throwing
+a `MethodError` if this type is not supported by either the display(s) or by `x`. With these
+variants, one can also supply the "raw" data in the requested MIME type by passing
+`x::AbstractString` (for MIME types with text-based storage, such as text/html or
+application/postscript) or `x::Vector{UInt8}` (for binary MIME types).
+"""
 function display(x)
  for i = length(displays):-1:1
  if xdisplayable(displays[i], x)
@@ -251,6 +285,19 @@ end
 # for Matlab/Pylab-like stateful plotting interfaces, where
 # a plot is created and then modified many times (xlabel, title, etc.).
 
+"""
+ redisplay(x)
+ redisplay(d::Display, x)
+ redisplay(mime, x)
+ redisplay(d::Display, mime, x)
+
+By default, the `redisplay` functions simply call [`display`](@ref).
+However, some display backends may override `redisplay` to modify an existing
+display of `x` (if any).
+Using `redisplay` is also a hint to the backend that `x` may be redisplayed
+several times, and the backend may choose to defer the display until
+(for example) the next interactive prompt.
+"""
 function redisplay(x)
  for i = length(displays):-1:1
  if xdisplayable(displays[i], x)