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-Hi. In this video, we are going to have
another look at the Inspector,

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and especially
how it can create the specific tabs

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that we have seen in the last
presentation of the Inspector.

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I will reuse the example that we defined
with the other dictionary,

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Time, Date, Morph.
And if we look back at the date,

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we can see that the time calendar
holding the calendar morph

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is actually defined
if we use a tool called Finder.

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Since the Inspector
is called the gtInspector,

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we will look for gtInspector
in the Pragmas.

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You can see this pragma called
"gtInspectorPresentationOrder".

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If I double click on this one,

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it will open the different senders
of his pragma,

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and if I look for a date,
we can see that it is called,

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within gtInspector, PreviewIn.
If I click on this,

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you can see that there is the creation
of a composite morph

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with a title "Calendar",
and using the morph "CalendarMorph".

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This is how this tab is defined there.

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We have got the Calendar title
and the CalendarMorph under it.

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Now, if we look at other objects such as
"Morph new Inspect" and press Cmd+D.

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This time, we have got a tab Morph
that depicts the actual morph,

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and you can see on the right
some actions.

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"Export as PNG" or "Delete".

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We will try to find those there
by searching for Morph.

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You can see that we have got
gtInspectorMorphIn,

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and if we look into his code,

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we can see that we have got
the same composite morph with a title,

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and the display of his image,

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and error handling
if it cannot draw the actual morph.

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Then, the two buttons
that can be found there,

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"Export as PNG" and "Delete",
that are defined underneath.

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The last one we are going to look at
is a compiled method.

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We will look at "Point>>#degrees"
and press Cmd+I to inspect it.

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You can see that this one
has several tabs.

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It has Bytecode, basically
all the instructions sent to the machine.

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So, send the instruction ">=",
"jumpFalse", "pushConstant".

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The Source. This is the actual
source code of the method.

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The intermediate representation,
and an abstract syntax tree.

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Those are extremely interesting.
What we can do, if I extend this a bit,

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we can go to Raw,
open another view of a same object,

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go to Bytecode on this one,
go to Source on this one.

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And a nice thing, if I click on,
for example, this instruction,

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"pushConstant: 0", it will highlight
the corresponding piece of source code.

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So, this is extremely nice
for developers of a compiler

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or if you are simply interested
in how the bytecode

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is translated into the source code
and vice versa.

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This is interesting and we will look
at how it is implemented.

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It is implemented under CompiledCode.
It is right there.

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You can see that we have got
the gtInspectorAST

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that is implementing the AST tab.

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The Bytecode tab is implemented there.

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The Bytes, Header,
Ir, Pragmas and so on.

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Everything is implemented there
using the gtInspector presentation order.

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This video was there
to show you that you can find

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how the tabs are implemented

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and that the Inspector
is really interesting

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to display a particular view
of the objects that you find.