at:tutorial:basic
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at:tutorial:basic [2007/04/17 17:10] – tvcutsem | at:tutorial:basic [2007/04/17 17:25] – tvcutsem | ||
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===== Blocks ===== | ===== Blocks ===== | ||
- | In AmbientTalk, | + | In AmbientTalk, |
< | < | ||
{ |< | { |< | ||
</ | </ | ||
- | If the block do not require any parameter, the |< | + | |
+ | If the block does not require any parameter, the |< | ||
< | < | ||
- | >{| a, b| a+ b} (3,2) | + | >{|a, b| a+ b}(3,2) |
>>5 | >>5 | ||
</ | </ | ||
Note that the argument list passed to the block can define the different types of arguments previously explained. | Note that the argument list passed to the block can define the different types of arguments previously explained. | ||
< | < | ||
- | >{|a, b, @rest| | + | >def sum := {|a, b, @rest| |
def total := a + b; | def total := a + b; | ||
| | ||
- | | + | }; sum(1,2,3) |
>>6 | >>6 | ||
</ | </ | ||
Line 230: | Line 231: | ||
This example also illustrates that blocks are also used to iterate over enumerations, | This example also illustrates that blocks are also used to iterate over enumerations, | ||
- | AmbientTalk | + | < |
+ | AmbientTalk | ||
+ | </ | ||
+ | |||
+ | ===== Keywords ===== | ||
+ | |||
+ | AmbientTalk supports keyworded messages, as in Smalltalk and Self. We have already seen some examples | ||
< | < | ||
- | > | + | > |
- | >>< | + | def i := 0; |
- | > | + | def mapped[tbl.length] |
- | >>9 | + | clo(tbl[i: |
+ | }; | ||
+ | } | ||
+ | >> < | ||
</ | </ | ||
- | ===== Keywords ===== | + | It can be invoked as follows: |
+ | < | ||
+ | >map: square onto: [1,2,3] | ||
+ | >> | ||
+ | </ | ||
- | AmbientTalk supports keyword messages. We have already seen some examples of keyword messages in the previous sections such as the foreach structure. | + | In AmbientTalk |
< | < | ||
def foo: arg1 bar: arg2 {...} | def foo: arg1 bar: arg2 {...} | ||
- | def foo: | ||
</ | </ | ||
+ | is transformed into: | ||
+ | < | ||
+ | def foo: | ||
+ | </ | ||
+ | |||
+ | However, it is impossible to directly call or define a keyworded function in a canonical style. | ||
===== Native Data Types ===== | ===== Native Data Types ===== | ||
- | + | The basic data types in AmbientTalk are numbers | |
- | The basic types in AmbientTalk are numbers, fractions, text, tables and booleans. In fact, these data types are nothing but objects and as such, they respond to a variety of native methods. Objects will be the subject of the next chapter of the tutorial. This section explains the basic data types and includes some examples how to manipulate them. The complete list of methods can be found in the language reference. | + | |
==== Numerical data types ==== | ==== Numerical data types ==== | ||
- | AmbientTalk supports numbers and fractions which represent what other languages call integers and floating point numbers, respectively. | + | AmbientTalk supports numbers and fractions which represent what other languages call integers and double precision |
- | Note that since numerical types are objects in AmbientTalk, | + | Note that since numerical types are objects in AmbientTalk, |
< | < | ||
>1.inc() | >1.inc() | ||
>>2 | >>2 | ||
- | > | ||
- | >>1 | ||
>1.cos() | >1.cos() | ||
>> | >> | ||
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>>2 | >>2 | ||
</ | </ | ||
+ | |||
+ | Beware of the precedence rules for function application versus method invocation, which may lead to unexpected results, e.g.: | ||
+ | </ | ||
+ | > | ||
+ | >>-1 | ||
+ | < | ||
+ | This code is interpreted as '' | ||
Numbers also support some useful iterator methods such as: | Numbers also support some useful iterator methods such as: |
at/tutorial/basic.txt · Last modified: 2020/02/09 22:05 by elisag