Modules

A program of any size uses code it did not write: the standard library, libraries of your own, packages from other people. tiko organises that code in modules. A module is compiled once, shows the world only the names it marks public, and keeps those names behind its own name, so two modules can both have a Parse without colliding.

The standard library is a set of modules. You bring one into a file with #import, and reach its names through the module's name:

'' Each #import names a module of the standard library. The imports
'' come first in the file, before any other code.
#import "std/strings"
#import "std/containers"

'' A module's names are reached through the module's name.
print strings.Replace( "a-b-c", "-", " + " )
print strings.StartsWith( "tiko-lang", "tiko" )
print strings.Format( "{} has {} letters", "module", len( "module" ) )

'' Types are reached the same way.
dim words as containers.Array( of ustring )
words.Push( "pear" )
words.Push( "apple" )
words.Push( "fig" )
print "words:"; words.Count( )

Output

a + b + c
true
module has 6 letters
words: 3

#import "std/strings" binds the name strings, the last part of the path. After it, strings.Replace is the Replace procedure of that module, and containers.Array( of ustring ) is its Array type. A value of a module's type behaves like one of your own: words.Push and words.Count need no prefix, because a method belongs to its type.

Two rules apply to every import:

• #import comes before any other code in the file, including #define lines. An #import further down is TKO0362, "'#import' must come before any code".
• The path is quoted and uses / on every platform.

There is nothing to list on the command line: tiko importing.tiko reads the imports, builds each module it needs (or takes it from the build cache), and links the result.

The rest of this section shows how to use names without the prefix, write a module, decide what it exposes, pass imports on, group modules into packages, and keep names apart inside one file with namespaces.

Activities

1. Print strings.Reverse( "tiko" ).
2. Move one #import line below the first print and read the diagnostic.