shithub: limbobyexample

Info  •  Files  •  Log

add arrays example

--- a/Arrays/README.md

+++ b/Arrays/README.md

@@ -8,32 +8,42 @@

 ### arrays.b:20,30

+This shows the initialization of an array of integers using a variable, `width`, as the count of elements for the array. 

+Note that on `arrays.b:13,15` the array of integers, `nums`, and the integer, `width`, are declared. 

 ### arrays.b:32,44

+Limbo supports indexing strings. The length, as per `len`, of a string is equivalent to the number of utf-8 runes within a given string. All strings in Limbo are utf-8 strings. 

+This section demonstrates the copying of a string into an array of bytes. 

 ### arrays.b:46,57

+Since the size of arrays is dynamic, one can declare an array to the size of a dynamic value. The array of bytes, `dbl`, is initialized to double the size of the array `arr`. 

+Each index of `arr` is copied to two neighboring indices in `dbl`. 

 ### arrays.b:59,67

+Arrays can be initialized to a given set of values as well. In this case, the characters `[a-f]` are used as values to populate the array of strings, `chars`. The size of the array will be equal to the number of elements provided in the aforementioned set. 

-

 ### arrays.b:69,84

+Arrays can be declared to be arrays of other arrays. In this case, the array `nest` is an array of four arrays of strings of size `2 << i`. 

+### arrays.b:86,97

-### arrays.b:86,94

+Arrays can be conditionally initialized to values. The syntax is similar to the `case` statement syntax. In this case, the first three indices are initialized to the byte value of 4. Indices three and greater are initialized to the byte value of 0.

+Note: Multiple conditional sections are not necessary to initialize to a given value. 

+### arrays.b:99,123

-### arrays.b:96,122

+This shows the declaration of an array of size 4 containing lists of string pairs. The lists begin as empty lists, comparable to nil. 

+The lists at indices 0 and 2 are prepended with pairs of strings. The head of the respective lists are then printed by extracting the pairs of strings prepended previously. 

-

 ## Demo

 	; limbo arrays.b

@@ -56,7 +66,7 @@

 	Lens: [ 2 4 8 16]

 	Len buf: 10

-	[ 3 3 3 3 3 3 3 3 3 3]

+	[ 4 4 4 3 3 3 3 3 3 3]

 	Len two: 4

 	Lens: [ 1 0 1 0]

@@ -66,4 +76,5 @@

 ## Exercises

 - Play with the widths of different arrays, what happens?

-- What can you initialize with the `* =>` operator, what can't you?

+- What can you initialize to with the `* =>` operator, what can't you?

+- Remove a case section from the `* =>` operator section, are all indices set to that value?

--- a/Arrays/arrays.b

+++ b/Arrays/arrays.b

@@ -84,7 +84,10 @@

 	print("]\n\n");

 	# Buf

-	buf := array[10] of {* => byte 3};

+	buf := array[10] of {

+		0 to 2 => byte 4,

+		* => byte 3

+	};

 	print("Len buf: %d\n", len buf);

@@ -95,8 +98,6 @@

 	# Two

 	two := array[4] of list of (string, string);

-

-	#two = array[4] of list of (string, string);

 	two[0] = ("ducks", "quack") :: two[0];

--- a/README.md

+++ b/README.md

@@ -34,6 +34,7 @@

 - [Loops](./Loops)

 - [If Else](./If-Else)

 - [Switch Case](./Switch)

+- [Arrays](./Arrays)

 ## References