hoon-school-live--2022-02.md

After Lesson 0, you should be able to:

• Explain what an Urbit ship is.
• Identify the .urb/ directory.
• Distinguish a fakeship from a liveship.
• Use the +ls generator to show a directory's contents.
• |mount and |commit a desk.

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After Lesson 1, you should be able to:

• Distinguish nouns, cells, and atoms.
• Apply auras to transform an atom.
• Identify common Hoon molds, such as cells, lists, and tapes.
• Annotate Hoon code with comments.
• Pin a face to the subject.
• Make a decision at a branch point.
• Distinguish loobean from boolean operations.
• Slam a gate (call a function).
• Produce a generator to convert a value between auras.
• Pronounce ASCII characters per standard Hoon developer practice.

You will know the runes:

• ::
• %-
• =/
• ?:
• ^-
• ~&
• ``

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After Lesson 2, you should be able to:

• Identify current known irregular syntax.
• Convert between regular and irregular forms of runes to date.
• Identify a mold in the hierarchy of Urbit types (nouns, molds, marks).
• Understand how type inference and type checking takes place.
• Bunt a mold.
• Produce a type union.
• Produce a named tuple.
• Identify type using !>.
• Identify common Hoon patterns: atoms, cells, cores, faces, and traps.
• Identify cores as [battery payload] cells.
• Produce a gate as a generator.
• Build code samples with -build-file thread.
• Discuss Ford import runes.

You will know the runes:

• ^+
• $?
• $_
• $:
• ^*
• !>
• |=
• !!
• /-
• /*
• /=

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After Lesson 3, you should be able to:

• Employ a trap to produce a reentrant block of code.
• Produce a recursive gate.
• Distinguish head and tail recursion.
• Consider Hoon structures as cores.
• Identify the special role of the $ buc arm in many cores.
• Order neighboring cores within the subject for addressibility.
• Address nodes in a tree using numeric notation.
• Address nodes in a tree using lark notation.
• Address data in a tree using faces.
• Distinguish . and : notation.
• Diagram Hoon structures such as gates into the corresponding abstract syntax tree.

You will know the runes:

• |-
• .+
• %=
• |%
• ++
• =<
• =>
• =+

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After Lesson 4, you should be able to:

• Use lists to organize data.
• Convert between kinds of lists (e.g. tapes).
• Diagram lists as binary trees.
• Operate on list elements using snag, find, weld, etc.
• Import a library using /+ faslus.
• Create a new library in /lib.
• Review Unicode text structure.
• Distinguish cords and tapes and their characteristics.
• Transform and manipulate text using text conversion arms.
• Interpolate text.
• Employ sigpam logging levels.

You will know the runes:

• /+
• ~& >>>

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After Lesson 5, you should be able to:

• Identify the structure of a door and relate it to a core.
• Pull an arm in a door.
• Identify the $ buc arm in several structures and its role.
• Review Unicode text structure.

You will know the runes:

• |_
• %~
• |.

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After Lesson 6, you should be able to:

• Use assertions to enforce type constraints.
• Identify a lest (as opposed to a list).
• Produce a type arm.
• Identify units, sets, maps, and compound structures like jars and jugs.
• Explain why units and vases are necessary.
• Use helper arms and syntax: `, biff, some, etc.

You will know the runes:

• ?>
• ?<
• ?~
• +$

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After Lesson 7, you should be able to:

• Produce loobean expressions.
• Reorder conditional arms.
• Switch against a union with or without default.
• Reel, roll, turn a list.
• Curry, cork functions.
• Change arity of a gate.

You will know the runes:

• ?|
• ?&
• ?!
• ?.
• ?-
• ?+
• ;:

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After Lesson 8, you should be able to:

• Create a %say generator.
• Identify how Dojo sees and interprets a generator as a cell with a head tag.
• Identify the elements of a sample for a %say generator.
• Produce a %say generator with optional arguments.
• Discuss stateful v. stateless applications and path dependence.
• Enumerate Hoon's tools for dealing with state: =. tisdot, =^ tisket, ;< micgal, ;~ micsig.
• Defer a computation.

You will know the runes:

• :-
• =.
• =^
• ;<
• ;~

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After Lesson 9, you should be able to:

• Distinguish errors, faults, and failures.
• Distinguish latent, masked, and manifest errors.
• Enumerate and identify common error messages.
• Employ a debugging strategy to identify and correct errors in Hoon code.
• Run existing unit tests.
• Produce a unit test.
• Produce a desk suitable for distribution.
• Install and distribute software using Grid.
• Explain elements of a docket file.

You will know the runes:

• !:
• !.