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Crystal
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Crystal
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if
if
As a suffix
As an expression
Ternary if
if var
if var.is_a?(...)
if var.responds_to?(...)
if var.nil?
if !
unless
case
while
while
break
next
until
&&
||
Requiring files
Types and methods
Types and methods
Everything is an object
The Program
Classes and methods
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new, initialize and allocate
Methods and instance variables
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Splats and tuples
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Visibility
Inheritance
Inheritance
Virtual and abstract types
Class methods
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finalize
Modules
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Blocks and Procs
Blocks and Procs
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Proc literal
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Closures
alias
Exception handling
Type grammar
Type reflection
Type reflection
is_a?
nil?
responds_to?
as
as?
typeof
Macros
Macros
Macro methods
Hooks
Fresh variables
Annotations
Annotations
Built-in annotations
Low-level primitives
Low-level primitives
pointerof
sizeof
instance_sizeof
offsetof
Uninitialized variable declaration
Compile-time flags
Compile-time flags
Cross-compilation
C bindings
C bindings
lib
fun
fun
out
to_unsafe
struct
union
enum
Variables
Constants
type
alias
Callbacks
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Conventions
Conventions
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Documenting code
Database
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Transactions
Guides
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Performance
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Testing
Writing Shards
Writing Shards
Hosting on GitHub
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Continuous Integration
Using Travis CI
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Static Linking
Platform Support
Tutorials
Tutorials
Basics
Basics
Hello World
Variables
Math
Strings
Control Flow
Methods
Tutorials
¶
The tutorials section contains introductory courses and lessons for the language.