Essentials - HackMD

# Essentials ## Introduction The Julia standard library contains a range of functions and macros appropriate for performing scientific and numerical computing, but is also as broad as those of many general purpose programming languages. Additional functionality is available from a growing collection of available packages. Functions are grouped by topic below. Some general notes: * Except for functions in built-in modules (`Pkg`, `Collections`, `Test` and `Profile`), all functions documented here are directly available for use in programs. * To use module functions, use `import Module` to import the module, and `Module.fn(x)` to use the functions. * Alternatively, `using Module` will import all exported `Module` functions into the current namespace. * By convention, function names ending with an exclamation point (`!`) modify their arguments. Some functions have both modifying (e.g., `sort!`) and non-modifying (`sort`) versions. ## Getting Around ```@docs Base.exit Base.quit Base.atexit Base.atreplinit Base.isinteractive Base.whos Base.summarysize Base.edit(::AbstractString, ::Integer) Base.edit(::Any) Base.@edit Base.less(::AbstractString) Base.less(::Any) Base.@less Base.clipboard(::Any) Base.clipboard() Base.reload Base.require Base.compilecache Base.__precompile__ Base.include Base.include_string Base.include_dependency Base.Docs.apropos Base.which(::Any, ::Any) Base.which(::Symbol) Base.@which Base.methods Base.methodswith Base.@show Base.versioninfo Base.workspace ans ``` ## All Objects ```@docs Core.:(===) Core.isa Base.isequal(::Any, ::Any) Base.isequal(::Nullable, ::Nullable) Base.isless Base.isless(::Nullable, ::Nullable) Base.ifelse Base.lexcmp Base.lexless Core.typeof Core.tuple Base.ntuple Base.object_id Base.hash Base.finalizer Base.finalize Base.copy Base.deepcopy Core.isdefined Base.convert Base.promote Base.oftype Base.widen Base.identity ``` ## Types ```@docs Base.supertype Core.issubtype Base.:(<:) Base.:(>:) Base.subtypes Base.typemin Base.typemax Base.realmin Base.realmax Base.maxintfloat Base.sizeof(::Type) Base.eps(::Type{<:AbstractFloat}) Base.eps(::AbstractFloat) Base.promote_type Base.promote_rule Core.getfield Core.setfield! Base.fieldoffset Core.fieldtype Base.isimmutable Base.isbits Base.isleaftype Base.typejoin Base.typeintersect Base.Val Base.Enums.@enum Base.instances ``` ## Generic Functions ```@docs Core.Function Base.method_exists Core.applicable Core.invoke Base.invokelatest Base.:(|>) Base.:(∘) ``` ## Syntax ```@docs Core.eval Base.@eval Base.evalfile Base.esc Base.@inbounds Base.@inline Base.@noinline Base.gensym Base.@gensym Base.@polly Base.parse(::Any, ::Any) Base.parse(::Any) ``` ## Nullables ```@docs Base.Nullable Base.get(::Nullable, ::Any) Base.isnull Base.unsafe_get ``` ## System ```@docs Base.run Base.spawn Base.DevNull Base.success Base.process_running Base.process_exited Base.kill(::Base.Process, ::Integer) Base.Sys.set_process_title Base.Sys.get_process_title Base.readandwrite Base.ignorestatus Base.detach Base.Cmd Base.setenv Base.withenv Base.pipeline(::Any, ::Any, ::Any, ::Any...) Base.pipeline(::Base.AbstractCmd) Base.Libc.gethostname Base.getipaddr Base.Libc.getpid Base.Libc.time() Base.time_ns Base.tic Base.toc Base.toq Base.@time Base.@timev Base.@timed Base.@elapsed Base.@allocated Base.EnvHash Base.ENV Base.is_unix Base.is_apple Base.is_linux Base.is_bsd Base.is_windows Base.Sys.windows_version Base.@static ``` ## Errors ```@docs Base.error Core.throw Base.rethrow Base.backtrace Base.catch_backtrace Base.assert Base.@assert Base.ArgumentError Base.AssertionError Core.BoundsError Base.DimensionMismatch Core.DivideError Core.DomainError Base.EOFError Core.ErrorException Core.InexactError Core.InterruptException Base.KeyError Base.LoadError Base.MethodError Base.NullException Core.OutOfMemoryError Core.ReadOnlyMemoryError Core.OverflowError Base.ParseError Base.ProcessExitedException Core.StackOverflowError Base.SystemError Core.TypeError Core.UndefRefError Core.UndefVarError Base.InitError Base.retry Base.ExponentialBackOff ``` ## Events ```@docs Base.Timer(::Function, ::Real, ::Real) Base.Timer Base.AsyncCondition Base.AsyncCondition(::Function) ``` ## Reflection ```@docs Base.module_name Base.module_parent Base.current_module Base.fullname Base.names Core.nfields Base.fieldnames Base.fieldname Base.datatype_module Base.datatype_name Base.isconst Base.function_name Base.function_module(::Function) Base.function_module(::Any, ::Any) Base.functionloc(::Any, ::Any) Base.functionloc(::Method) Base.@functionloc ``` ## Internals ```@docs Base.gc Base.gc_enable Base.macroexpand Base.@macroexpand Base.expand Base.code_lowered Base.@code_lowered Base.code_typed Base.@code_typed Base.code_warntype Base.@code_warntype Base.code_llvm Base.@code_llvm Base.code_native Base.@code_native Base.precompile ```

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