diff options
Diffstat (limited to 'janet.html.markdown')
| -rw-r--r-- | janet.html.markdown | 51 |
1 files changed, 27 insertions, 24 deletions
diff --git a/janet.html.markdown b/janet.html.markdown index 7b2912c2..62ed7331 100644 --- a/janet.html.markdown +++ b/janet.html.markdown @@ -29,9 +29,9 @@ nil # Typical style for symbols (identifiers-for / names-of things). do-stuff pants-on-fire! -foo->bar # Evidently for converting foos to bars. +foo->bar # Evidently for converting foos to bars. fully-charged? -_ # Usually used as a dummy variable. +_ # Usually used as a dummy variable. # Keywords are like symbols that start with a colon, are treated like # constants, and are typically used as map keys or pieces of syntax in @@ -58,10 +58,11 @@ math/e # => 2.71828 "hello" "hey\tthere" # contains a tab -# For multi-line strings, use one or more backticks. No escapes allowed. +# For multi-line strings, use one or more backticks. Backslash-escapes not +# recognized in these (bytes will be parsed literally). ``a long multi-line -string`` # => "a long\nmulti-line\nstring" +string`` # => "a long\nmulti-line\nstring" # Strings and data structures in Janet come in two varieties: mutable and # immutable. The literal for the mutable variety is written with a `@` in @@ -72,7 +73,7 @@ string`` # => "a long\nmulti-line\nstring" @`a multi-line one here` -(string "con" "cat" "enate") # => "concatenate" +(string "con" "cat" "enate") # => "concatenate" # To get a substring: (string/slice "abcdefgh" 2 5) # => "cde" @@ -81,7 +82,8 @@ one here` # See the string library for more (splitting, replacement, etc.) -# Arrays and Tuples ########################################################### +# Data Structures ############################################################# +# Arrays and Tuples # Arrays are mutable, tuples are immutable. # Arrays (mutable) @@ -91,18 +93,19 @@ one here` # Tuples (immutable) # Note that an open paren usually indicates a function call, so if you want a # literal tuple with parens, you need to "quote" it (with a starting single -# quote mark). +# quote mark)... '(4 5 6) [4 5 6] # ... or just use square brackets. -# Tables and Structs (AKA: "maps", "hashmaps", "dictionaries") +# Tables and Structs (associative data structures) @{:a 1 :b 2 :c 3} # table (mutable) {:a 1 :b 2 :c 3} # struct (immutable) +# To "pretty-print" these out, use `pp` instead of `print`. # More about how to work with arrays/tuples and tables/structs below. # Bindings #################################################################### -# ... or "Name Some Things!" (that is, bind a value to a symbol) +# Bind a value to a symbol. (def x 4.7) # Define a constant, `x`. x # => 4.7 (quote x) # => x (the symbol x) @@ -113,7 +116,7 @@ x # => 4.7 (set x 5.6) # Error, `x` is a constant. (var y 10) -(set y 12) # Works, since `y` was made var. +(set y 12) # Works, since `y` was defined using `var`. # Note that bindings are local to the scope they're called in. `let` # creates a local scope and makes some bindings all in one shot: @@ -151,29 +154,29 @@ insect-friend # => bee (% 5 3) # => 2 (remainder) (- 5) # => -5 (or you can just write `-5`) -(++ i) # increments +(++ i) # increments (modifies `i`) (-- i) # decrements (+= i 3) # add 3 to `i` (*= i 3) # triple `i` # ... and so on for the other operations on numbers. +# If you don't want to mutate `i`, use `(inc i)` and `(dec i)`. + # Comparison # = < > not= <= >= (< 2 7 12) # => true # Functions ################################################################### # Call them: -(- 5 3) # => 2 (Yes, operators and functions work the same.) +(- 5 3) # => 2 (Operators and functions work the same way.) (math/sin (/ math/pi 2)) # => 1 -(range 5) # => @[0 1 2 3 4] +(range 5) # => @[0 1 2 3 4] # Create them: (defn mult-by-2 ``First line of docstring. - Some more of the docstring. - - Possibly more!`` + Some more of the docstring.`` [x] (print "Hi.") (print "Will compute using: " x) @@ -206,7 +209,7 @@ n # => 3 # You might say that function bodies provide an "implicit do". # Operations on data structures ############################################### -# (Making all these mutable so we can ... mutate them.) +# (Making all of these mutable so we can ... mutate them.) (def s @"Hello, World!") (def a @[:a :b :c :d :e]) (def t @{:a 1 :b 2}) @@ -216,9 +219,9 @@ n # => 3 (length t) # => 2 # Getting values: -(s 7) # => 87 (which is the code point for "W") -(a 1) # => :b -(t :a) # => 1 +(s 7) # => 87 (which is the code point for "W") +(a 1) # => :b +(t :a) # => 1 (keys t) # => @[:a :b] (values t) # => @[1 2] @@ -227,14 +230,14 @@ n # => 3 (put a 2 :x) # @[:a :b :x :d :e] (put t :b 42) # @{:a 1 :b 42} -# Adding & removing values (again, for mutable data structures): +# Adding and removing values (again, for mutable data structures): (buffer/push-string s "??") # @"HeWlo, World!??" (array/push a :f) # @[:a :b :x :d :e :f] (array/pop a) # => :f, and it's also removed from `a`. (put t :x 88) # @{:a 1 :b 42 :x 88} # See the manual for a wide variety of functions for working with -# buffers/strings, arrays/tuples, and tables/struct. +# buffers/strings, arrays/tuples, and tables/structs. # Flow control ################################################################ (if some-condition @@ -282,7 +285,7 @@ n # => 3 {:yar v} (print "matches key :yar! " v) {:moo v} (print "matches key :moo! " v) {:c v} (print "matches key :c! " v) - _ (print "no match")) # => prints "matches key :c! 3" + _ (print "no match")) # => prints "matches key :c! 3" # Iterating ################################################################### # Iterate over an integer range: @@ -312,7 +315,7 @@ n # => 3 (* x x)) (range 10))) # => @[0 4 16 36 64] -(reduce + 0 (range 5)) # => 10 +(reduce + 0 (range 5)) # => 10 # ...and lots more (see the API docs). |