[[Property:modification_date|Tue, 09 Jul 2019 09:52:07 GMT]]
[[Property:publication_date|Tue, 09 Jul 2019 09:46:53 GMT]]
[[Property:title|Differences between standard ECMA-367 and Eiffel Software implementation]]
[[Property:link_title|ECMA-367 vs implementation]]
[[Property:weight|-10]]
[[Property:uuid|0eb58761-5b06-585f-ea92-cab2b8cd74b2]]
"ETL 2" refers to the book "Eiffel: The Language" (2nd printing), published by Prentice Hall.
==Kernel classes==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Fictitious class for tuples
| TUPLE
| No
| Yes
| Yes
|}
==Features==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Prefix and infix feature names
| infix "+"
| Yes
| No
| Yes, marked as obsolete
|-
| Operator and bracket aliases
| add alias "+"
| No
| Yes
| Yes, except for new rules
for free operator names
|-
| Assigner command
| item alias "[]" (index: INTEGER): G assign put
| No
| Yes
| Yes
|}
==Design by Contract==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Only postcondition clauses
| ensure only a, b
| No
| Yes
| No
|}
==Genericity==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Mutually recursive constraints
| A [H, G -> H]
B [H -> C, G -> ARRAY [H]]
| No
| Yes
| Yes
|-
| Full mutually recursive constraints
| A [H -> G, G -> H]
| No
| Yes
| Yes
|-
| Expandedness restriction on formal generic
| A [reference G]
B [expanded H]
| No
| No
| Yes
|}
==Creating objects==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Implicit creation procedure (version of
ANY.default_create)
| class A feature ... end
-- The following instructions are equivalent:
create {A} a
create {A} a.default_create
| No
| Yes
| Yes
|-
| Bang-bang syntax
| !! a
!! a.make
!B! a
!B! a.make
| Yes
| No
| Yes, marked as obsolete
|-
| Keyword syntax
| create a
create a.make
create {B} a
create {B} a.make
| No
| Yes
| Yes
|-
| Creation expression
| print (create {TIME}.make_now)
| No
| Yes
| Yes
|-
| [[ET: Genericity and Arrays|Generic creation]]
| create {G} x.make
| No
| Yes
| Yes
|}
==Attachment==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Preserving expandedness status
when attaching expanded object
to reference entity
| x := y
| No, object is copied to new
object of the corresponding
reference type
| Yes
| Yes, except for TYPED_POINTER
that is converted to POINTER before
reattachment
|-
| Reverse assignment (assignment attempt)
| x ?= y
| Yes
| No
| Yes. Marked as obsolete (V7.1).
|}
==Feature calls==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Precursor call
| Precursor
| No
| Yes
| Yes
|-
| Non-object call
| c := {COLOR}.green
| No
| Yes
| Yes
|-
| Assigner call
| x [i] := x [i] + 1
| No
| Yes
| Yes
|-
| Bracket expression as call target
| x [i].update
| No
| No
| Yes
|}
==Void-safety==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Attachment marks
| a: attached ANY
b: detachable ANY
| No
| Yes, attached by default
| Yes, attached by default
|-
| Object test
| attached {STRING} e as o
| No
| Yes
| Yes
|-
| Attached target of a call
| x.f
| No
| Yes
| Yes, by option ''void_safety''
|-
| Properly set variable
| x := value
use (x)
| No
| Yes
| Yes, by option ''void_safety''
|}
==[[Concurrent programming with SCOOP|SCOOP]]==
{| class="doctable"
|-
! '''Feature'''
! width="160pt"| '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Separate declaration
| a: separate ANY
| No
| No. separate reserved but not used
| Yes. Object attached to a may be handled by different SCOOP processor.
|}
==Expressions==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Bracket expression
| y := x [i]
| No
| Yes
| Yes
|-
| Creation expression
| set_buffer (create {STRING}.make (100))
| No
| Yes
| Yes
|-
| Manifest type
| {MY_TYPE}
| No
| Yes
| Yes
|-
| Manifest [[ET: Other Mechanisms|tuple]]
| [a, b, c]
| No
| Yes
| Yes
|-
| [[ET: Agents|Agent]]
| list.do_all (agent print (?))
| No
| Yes
| Yes
|-
| Once manifest string
| once "abc"
| No
| Yes
| Yes
|}
==Constants==
{| class="doctable"
|-
! '''Feature'''
! '''Example'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Verbatim string
|
x := "[
This string is left-adjusted.
]"
y := "{
This string is used "as is".
}"
| No
| Yes
| Yes
|-
| Manifest type qualifier
| {INTEGER_8} 123
| No
| Yes
| Yes
|-
| Non-decimal integer
| 0xFF
| No
| Yes
| Yes
|-
| Integer with intermediate underscores
| 1_000 0xFFFF_0000
| In groups by 3 digits
| Yes
| Yes
|}
==Interfacing with external software==
{| class="doctable"
|-
! '''Feature'''
! '''ETL2'''
! '''ECMA-367'''
! '''EiffelStudio'''
|-
| Access to software written in C
| Basic syntax for any external software
| Registered sub-language
| See details for [[C externals|C externals]].
|-
| Access to software written in C++
| Basic syntax for any external software
| Registered sub-language
| See details for [[C++ Externals|C++ externals]].
|-
| Access to dynamically loaded libraries (DLLs)
| Basic syntax for any external software
| Registered sub-language
| See details for [[uuid:4ad177dd-13ec-c237-99b3-efc9851995a5|Interfacing with DLLs]].
|-
| Other external software
| Basic syntax for any external software
| Unregistered sub-language
| No
|}