# Forum

• Apr 25
Re: [eiffel-users] Passing STRINGs to 'separate' objects
Thanks Alexander, well explained. On Thursday, 25 April 2019 07:55:11 UTC+1, Alexander Kogtenkov wrote: > > The difference between STRING types and numerical types is in the > reattachment semantics. STRING types have reference semantics, i.e. during > reattachment, a reference to the object is
• Apr 25
Re: [eiffel-users] Passing STRINGs to 'separate' objects
The difference between STRING types and numerical types is in the reattachment semantics. STRING types have reference semantics, i.e. during reattachment, a reference to the object is passed, there is just a single copy of that object. Basic numerical types (REAL_32, INTEGER, etc.) have copy
• Apr 24
Passing STRINGs to 'separate' objects
I'm trying to use SCOOP for the first time, and am having trouble making sense of the compiler messages. I have a class I wish to run concurrently: class RACE feature {NONE} -- Initialization starttime: STRING course: STRING going: STRING distance: REAL make (passed_st
• Apr 23
RE: Re[2]: [eiffel-users] another strange one
The problem is indeed quite specific, you're correct. I did some testing and I can save pretty much any EV_PIXMAP I choose, using the save_to_named_path and it works like a charm. There remains a CAT call problem when using save_to_named_file, having nothing to do with pixmaps, I suspect, but
• Apr 23
Re[2]: [eiffel-users] another strange one
The issue seems to be quite specific. For example, EiffelStudio uses EV_PIXMAP.save_to_named_path to export a diagram to the PNG format. It opens the target file for writing to check that this can be done, then it closes the file, and, finally, it calls save_to_named_path (create {EV_PNG_FORMAT
• Apr 23
RE: [eiffel-users] another strange one
Not so fast. While it's true, I did not see the CAT call when using save_to_named_path, I still failed to accomplish my objective. The issue is not related to the CAT call at all. I am attempting to create a simple image in a drawing area. So far, easy as pie. Then, I'm attempting to save the
• Apr 23
RE: [eiffel-users] another strange one
Hi I just tried the save_to_named_path equivalent and did not see the problem. R -------- Original Message -------- Subject: [eiffel-users] another strange one From: Date: Mon, April 22, 2019 7:09 pm To: "Eiffel Users Group" Hi All I dusted off a
• Apr 22
another strange one
Hi All I dusted off a feature I haven't used in, .. Never mind how long it's been. With 18.07, I tried saving a pixmap to a file using EV_PIXMAP.save_to_named_file (fmt, fname) Where: fmt was an instance of EV_PNG_FORMAT and fname was the ever-adventurous "test.png" The save_to_named_file
• Apr 20
Problems compiling Traffic library

I attempted to install the Traffic library for the book "A Touch of Class" but was not able to compile the examples. EiffelStudio complained about a base2.ecf file. Error code: VD00

General configuration parsing error. What to do: fix the configuration file.

Could not open file: \base2.ecf $EIFFELBASE2\base2.ecf base2.ecf is found in where Windows installed Eiffel: C:\Program Files\Eiffel Software\EiffelStudio 18.11 GPL\unstable\library\base2.ecf The offending line of code seems to be this in the Traffic configuration files: I have attempted to change this configuration file pointing directly to where the file is, using the actual path, to no avail. • Apr 13 RE: [eiffel-users] Re: pixmap transparency Hi Finnian The mere mention of SVG gets me all-a-twitter. Love them vectors, but (believe it or not) Windows is my platform of choice for such experiments, and I've moved to the more-or-less latest versions of stuff in that environment. I will, however, take a good long (or is that longing?) • Apr 13 RE: [eiffel-users] pixmap transparency Hi Manu Yes, I was hoping to use this as a widget (i.e. take the easy way out), but I can do the drawing approach. I'll give that a try. Thanks R -------- Original Message -------- Subject: Re: [eiffel-users] pixmap transparency From: Emmanuel Stapf Date: Sat, April 13, 2019 • Apr 13 Re: pixmap transparency I forgot to mention Eiffel-Loop also has an Image Utilities library that does not depend on Vision2. This library has two classes for rendering SVG. 1. EL_PNG_IMAGE_FILE (Recommended) 2. EL_SVG_IMAGE_UTILS Again the Windows implementation requires GTK dlls compiled with Mingw, • Apr 13 Re: pixmap transparency Hello Roger, there are some caveats but Eiffel-Loop has a solution for what you are asking. Specifically you can use class EL_DRAWABLE_PIXEL_BUFFER which serves as a wrapper for the Cairo 2D graphics library, and is compatible with Vision2 16.05. There is also a class for rendering SVG EL_SVG_PIX • Apr 13 Re: [eiffel-users] pixmap transparency Hi Roger, Are you using an EV_PIXMAP because you want to use it as a widget? In this case, I suggest using an EV_DRAWING_AREA and draw the EV_PIXEL_BUFFER object on it. There are some limitations with EV_PIXMAP as it represents two completely different paradigm: an image and a container with • Apr 12 pixmap transparency Hi All This is not a new topic, but I can't find a resolution, so here goes again. I need to be able to create transparent pixmaps (i.e. pixmaps that have some areas that are transparent). When working with EV_PIXMAPs , and applying an EV_BITMAP mask, the effect is only the mask or unmask the • Apr 10 Re: Can't compile EiffelBuild project You're welcome! • Apr 09 Re: Can't compile EiffelBuild project That sounds like good advice. Thanks! On Saturday, April 6, 2019 at 8:26:14 PM UTC-4, Larry Rix wrote: > > The other choice is to remove the precompile reference. We tended to shy > away from precompiles because of small issues. While there are simple > solutions and small problems, we found it • Apr 09 Re: EiffelBuild Tips Window dropping last word of each line The issue isn't with EiffelBuild, but the tool tip window that is part of EiffelBuild. I agree with your points on visual builders in general though. The bug in the Tip of the Day dialog doesn't affect the usability of the tool in any way. It just gives a bad first impression - makes one think • Apr 09 RE: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line Thanks Larry; I couldn't agree more. R -------- Original Message -------- Subject: Re: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line From: Larry Rix Date: Tue, April 09, 2019 11:22 am To: Eiffel Users The key • Apr 09 Re: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line The key to successful use of a generator is unchanging consistency. It hardly matters if code is hand-written or generated by a computer program. What counts is that the result is consistent in feature signature and naming. As long as it remains relatively constant, one can use the Bridge • Apr 09 RE: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line Thanks Larry. Does it help make up for my idiot-fest on missing libraries? :) I did have to do a fair amount up front to make it work with my custom vision classes, but by doing that, I ended up with a handy-dandy and relatively painless process. The key element is to have a kind of template • Apr 09 RE: Re[2]: [eiffel-users] stuck on process Mea Culpa. I might need to adjust my prescription (whether that's eyeglasses or something else, I leave to your imagination) Suffice to say they'll be revoking my keyboarding license after this one. Sorry for the confusion R -------- Original Message -------- Subject: Re[2]: [eiffel-users] stuck • Apr 09 Re: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line R! Now, this is an interesting post. I was unaware anyone had taken EiffelBuild seriously. Good for you! • Apr 09 Re[2]: [eiffel-users] stuck on process Indeed, this looks really strange. Could you send the ECF by a direct email or by submitting a bug report at support.eiffel.com? Thank you, Alexander Kogtenkov Понедельник, 8 апреля 2019, 22:05 +03:00 от r...@amalasoft.com: That makes sense, but what I am seeing does not. The base_process • Apr 08 RE: [eiffel-users] stuck on process That makes sense, but what I am seeing does not. The base_process library is included - as evidenced by it showing up in the libraries section of the screen shot I attached. Here are the entries from the .ecf file. Apr 08 stuck on process Hi All Perhaps the solution is obvious and I've just gone stupid, but it strikes me that this can't happen. I'm trying to access the process_factory function. Even after nuking EIFGENs, compiling from scratch, standing on one leg, and making noises like a chicken, the process classes seem to • Apr 08 Re: [eiffel-users] stuck on process You need to include "base_process" library in your project. At the moment it is included in the system, because some library (called "process") uses it. But classes of a library become accessible to the project classes only when the library is listed directly. Hope this helps, Alexander • Apr 07 RE: [eiffel-users] Re: EiffelBuild Tips Window dropping last word of each line I've used EiffelBuild quite a bit over the years, though not for an _end_product_. I have developed a library that works with what EiffelBuild creates, allowing me to bootstrap projects with EiffelBuild, and even make some GUI changes (using EiffelBuild) after incorporating almost entirely • Apr 07 Re: EiffelBuild Tips Window dropping last word of each line I am unaware of anyone using EiffelBuild for production. It does not seem to be an issue with EiffelBuild, but with Visual Builders in general. The perform poorly in several ways: - Difficult to integrate custom visual classes. - Impossible to show deterministic complex visual changes in • Apr 07 Re: Can't compile EiffelBuild project The other choice is to remove the precompile reference. We tended to shy away from precompiles because of small issues. While there are simple solutions and small problems, we found it easier to just not have precompiles at all. • Apr 06 Re: Can't compile EiffelBuild project Solved it, found a menu item called Tools | Precompilation Wizard... After running the wizard, the missing folder is created. On Saturday, April 6, 2019 at 1:48:49 PM UTC-4, Stephen Smith wrote: > > Error code: C Compiler Error > > Error: External C/C++ compilation failed. > What to do: Check the • Apr 05 Eiffel: passing argument to agent received as argument I'm really stuck in how to pass an argument to a second level of an Eiffel agent call. Hope my example is enough self explaining: main_call do b (agent d(?, ?)) end b (a_proc: PROCEDURE[STRING]) local l_something_else: INTEGER do l_something_else := 1 -- z("a_line", a_proc(l_something_else)) -- How can I pass at this stade l_something_else to the d procedure!!! end d (line: STRING; something_else: INTEGER) do -- do_some_stuff_with_line (line, something_else) do_nothing end z (a_line: STRING; a_proc: PROCEDURE[STRING]) do a_proc.call([a_line]) end  I would have liked to be able to do something like z("a_line", a_proc(?, something_else))  But its not possible, as I try with the agent keyword, the a_proc argument is not recognized! So what would be the syntax? I even tried to add an argument to a_proc with a_proc.set_operands but am lost with the OPEN_ARGS class ## Implementation case If you need a goal... just imagine I'd like to have 2 different implementations of the d function, and in my case its using UT_CSV_HANDLER that I'd like to have 2 different functions for each line of a CVS The following code gives a Non-compatible actual argument in feature call Feature: import_from_csv_impl Called feature: import_from_csv_impl (a_rest_request: REST_REQUEST; a_procedure: PROCEDURE [DS_ARRAYED_LIST [STRING_8], INTEGER_64, STRING_8]): [detachable like items] detachable SIT_LINKED_LIST [MEASURING_POINT] from MEASURING_POI... Argument name: ia_name Argument position: 2 Formal argument type: STRING_8 Actual argument type: INTEGER_64 Line: 258 ia_procedure.call (ia_measuring_point_id, ia_name) -> end (?, l_measuring_point_id, l_s) l_csv_handler.read_file (l_is, l_partially_closed)  The complete example: -- Main call import_from_abb_csv (a_rest_request: REST_REQUEST): detachable like items do Result := import_from_csv_impl (a_rest_request, agent impl_for_each_csv_line_import_from_abb_csv) end -- Second call import_from_csv_impl (a_rest_request: REST_REQUEST; a_procedure: PROCEDURE[DS_ARRAYED_LIST [STRING_8], INTEGER_64, STRING]): detachable like items local l_csv_handler: UT_CSV_HANDLER l_is: KL_STRING_INPUT_STREAM l_measuring_point_id: INTEGER_64 l_s: STRING l_partially_closed: PROCEDURE[DS_ARRAYED_LIST[STRING]] do l_s := "whatever" l_measuring_point_id := 12 create l_csv_handler.make_with_separator (',') l_partially_closed := agent (i_al: DS_ARRAYED_LIST[STRING]; ia_measuring_point_id: INTEGER_64; ia_name: STRING; ia_procedure: PROCEDURE[INTEGER_64, STRING]) do ia_procedure.call (ia_measuring_point_id, ia_name) end (?, l_measuring_point_id, l_s) l_csv_handler.read_file (l_is, l_partially_closed) end -- end call impl_for_each_csv_line_import_from_abb_csv (a_csv_line: DS_ARRAYED_LIST [STRING_8]; a_measuring_point_id: INTEGER_64; l_cu_name: STRING) do -- do_my_business end -- for information signature of read_file is: -- read_file (a_file: KI_TEXT_INPUT_STREAM; a_action: PROCEDURE [DS_ARRAYED_LIST [STRING]])  • Apr 05 Eiffel: type conformance, how to give a type instead of an instance ## General I don't understand why there are like 2 generating_type kinds, the one with exclamation point, and the other not. ## My case I have a function returning a DB_SERVICE[G] from a given instance from a collection of db_services so that from another service I can retrieve it and call it. When I pass an instance generating_type to that function, the conforms_to returns True, as when I give ({ENUMERATE}).generating_type it doesn't. Why is that so? -- Humanly unreadable if attached {ENUMERATE_DB_SERVICE} {SIT_ENVIRONMENT}.app_instance.db_service_from_entity_type (item_prototype.charge_unit_relationship.secondary_prototype.an_index_relationship.secondary_prototype.generating_type) as l_enum_dbs then -- Humanly readable but not working if attached {ENUMERATE_DB_SERVICE} {SIT_ENVIRONMENT}.app_instance.db_service_from_entity_type (({ENUMERATE}).generating_type) as l_enum_dbs then  My function db_service_from_entity_type (an_entity_type: TYPE[detachable DB_ENTITY]): detachable like db_services.item do across db_services as l_dbs until Result /= Void loop if l_dbs.item.item_prototype.generating_type.conforms_to (an_entity_type) then Result := l_dbs.item end end ensure service_found: attached Result end  ## Edit (20190405-11:26 UTC) As the screenshot shows, giving {ENUMERATE} instead of ({ENUMERATE}).generating_type doesn't work either • Mar 29 Eiffel: Creating a datetime with '' format Seems I'm wrong creating a datetime from string using this method, any idea why? The precondition violates on date_time_valid: date_time_valid (s, code) create l_date_time.make_from_string ("2019-03-28T15:28:02Z", "yyyy-mm-ddThh:mi:ssZ")  • Mar 10 Eiffel shortest statement for object creation and result of function If I'd like to add a DATE_TIME to a logger for example I'd like to avoid creating a local variable for that. Is there any similar statement as create {DATE_TIME}.make_now.formatted_out ("yyyy-mm-dd hh:mi:ss")  which is not possible? • Feb 18 Eiffel: a way to display assertion violation on runtime of executable As I have the choice on finalizing a project to keep assertions, I'd think that assertion violation would be shown or displayed on console (hopefully on stderr on linux). What would be the proper way to do such, like seems that I have to add it or enable something to get it... • Feb 11 Eiffel: how do I set the command line arguments of an autotest? Some of my tests needs something like {EXECUTION_ENVIRONMENT}.arguments.separate_character_option_value ('l')  to be attached (not Void), how do I set commandline arguments to eiffel autotest? • Feb 11 Eiffel: a proper way to inherit from a class and convert Current object to it It's not the first time I'm trying to inherit from a class and convert an object to it, in this case extend functionalities of HTTP_CLIENT_RESPONSE with valid_http_response => response.status = 200, valid_http_json_body => validate json content, etc... For that, I'd like to inherit from HTTP_CLIENT_RESPONSE and add features and create my custom DB_ENTITY_HTTP_CLIENT_RESPONSE from an HTTP_CLIENT_RESPONSE test_case local l_http_client_r: HTTP_CLIENT_RESPONSE l_db_entity_http_client_r: DB_ENTITY_HTTP_CLIENT_RESPONSE do l_http_client_r := execute_get("someURL") -- returns an HTTP_CLIENT_RESPONSE l_db_entity_http_client_r := l_http_client_r assert("valid response", l_db_entity_http_client_r.valid_response) end  it seems I've difficulties having the internal properties set... what would be the best way to do this? I had the same case trying to create a WATT class inheriting from NATURAL_32 which is an expanded. In my strategy, I tried to call in creator • a parent creation procedure • then call a deep_copy Here is the rest of my class attempt: class DB_ENTITY_HTTP_CLIENT_RESPONSE inherit HTTP_CLIENT_RESPONSE create make_from_http_client_response convert make_from_http_client_response ({HTTP_CLIENT_RESPONSE}) feature -- Initialization make_from_http_client_response (a_client_response: HTTP_CLIENT_RESPONSE) do make (a_client_response.url) deep_copy (a_client_response) end feature -- Status report valid_response: BOOLEAN do Result := status = 200 end  The only way I found working for now is by setting all attributes to other which is the semantic of deep_copy normally... make_from_http_client_response (a_client_response: HTTP_CLIENT_RESPONSE) do make (a_client_response.url) set_body (a_client_response.body) set_http_version (a_client_response.http_version) set_error_occurred (a_client_response.error_occurred) set_error_message (a_client_response.error_message) set_raw_header (a_client_response.raw_header) set_status_line (a_client_response.status_line) ... I surely forgot something... end  • Feb 10 Eiffel: is there a way with do_all or do_if to search for an element in a collection without having to write a whole feature? across collection as l_item until Result /= Void loop if l_item.item.name.is_equal ("foo") then Result := l_item.item end end  is there a way and if so which one to do something like collection.do_if (agent ...)  ## an example of use can be: search_item_with_id (an_id: INTEGER) -- Moves items cursor if not found is_after local l_found: BOOLEAN do from items.start until items.after or l_found loop l_found := items.item.primary_key = an_id if not l_found then items.forth end end ensure cursor_on_element_if_found: not items.after implies items.item.primary_key = an_id end  • Feb 01 Eiffel: ODBC Dealing with BIGINT ## Eiffel Seems I'm getting an INTEGER_32_REF from a BIGINT from ODBC with Eiffel DB_SELECTION.cursor. Sometimes I seem to have the adecuate value, but sometimes not... 946383958 => good INTEGER_32_REF (id->4 of following table) 9475984837 => 886050245 WRONG INTEGER_32_REF (id->4 of following table) 646383958 => good INTEGER_32_REF (id->3 of following table) 6475984837 => -2113949755 WRONG INTEGER_32_REF (id->4 of following table) ...  It seems to behave like not treating the BIGINT and giving the INTEGER_32_REF value directly interpreted from the DB value, typical case passing over the 2^32 ## Postgresql Having a table with following data as electricity_amount BIGINT NOT NULL DEFAULT 0 id | a_date | amount | electricity_amount | consumption_sector_id | electricity_rate_id ----+------------+-----------+--------------------+-----------------------+--------------------- 1 | 2019-01-01 | 746383958 | 7475984837 | 1 | 1 2 | 2019-02-01 | 846383958 | 8475984837 | 1 | 1 3 | 2019-03-01 | 646383958 | 6475984837 | 1 | 1 4 | 2019-04-01 | 946383958 | 9475984837 | 1 | 1  • Jan 31 Eiffel: non-compatible actual argument in feature call I don't understand why it is so. • If I say attached {G} it works • If I say nothing which would be the expected behavior for me calling_entity: detachable RELATED_DB_ENTITY should be conform (once attached) to G which is -> DB_ENTITY • If I say DB_ENTITY it doesn't • If I say RELATED_DB_ENTITY either does it pass Why do I have to specify {G}??? ## SIT_HANDLER class SIT_HANDLER[G -> DB_ENTITY create default_create, make_from_db_service, make_from_json end] feature -- some_feature do if attached {G} l_rest_request.calling_entity as l_calling_entity then db_service.set_item_prototype (l_calling_entity) -- Complains here!!!!!!!!!!!! db_service.load_with_relationships (l_rest_request) ... end end -- class  ## REST_REQUEST class REST_REQUEST feature -- Access calling_entity: detachable RELATED_DB_ENTITY -- RELATED_DB_ENTITY inherits DB_ENTITY ... end -- class  ## DB_SERVICE class DB_SERVICE [G -> DB_ENTITY create default_create, make_from_db_service, make_from_json end] feature -- Status setting item_prototype: G set_item_prototype (v: like item_prototype) do item_prototype := v ensure item_prototype = v end ... end -- class  • Jan 30 Eiffel: setting a constant with reference to other class constant How to set a constant refering to another class constant in Eiffel? Something like that doesn't compile unfortunately Default_log_level: like {MY_LOGGER}.log_level = {MY_LOGGER}.Log_level_info  • Jan 27 Eiffel: REAL_32.to_double gives a strange value Trying to transform a real_32 to real_64, I'm getting real_32: 61.55 real_64: 61.54999923706055  Am I wrong with the to_double function? • Jan 26 Eiffel: multilines string formating Didn't find a better way to format a multiline string than this way... seems complicated. What would be the best way to format this type of code? l_qry := "SELECT% % * % %FROM % % enumerate % %WHERE % % " + {like item_prototype}.Primary_key_db_column_name + " = " + l_category_id + " % %UNION % % SELECT % % e.* % % FROM % % enumerate e % %INNER JOIN % % enumerates_leaves s ON s." + {like item_prototype}.Primary_key_db_column_name + " = e." + {like item_prototype}.Category_db_column_name + " % %) SELECT * FROM enumerates_leaves WHERE enumerates_leaves." + {like item_prototype}.Category_db_column_name + " IS NOT NULL;"  • Jan 26 eiffel: does the across structure move the cursor of current iterable structure? I was wondering if the across structure uses an own cursor or a separated one? does it ensure that cursor hasn't moved and if so how can it be expressed for other examples? • Jan 25 Eiffel: how to use old keyword in ensure contract clause with detached How to use the old keyword into ensure clause of a feature, the current statement doesn't seem to be valid at runtime relationships: CHAIN -- any chain some_feature do (...) ensure relationship_added: attached relationships as l_rel implies attached old relationships as l_old_rel and then l_rel.count = l_old_rel.count end  ## For the whole case, following screenshots demonstrate the case start of routine execution end of routine execution • Jan 24 Eiffel: void safety, a concise way to test if an object exists and then call its feature I was wondering if there is a clearer statement then if not attached foo then create foo end if attached foo as l_foo then l_foo.bark end  as if not attached foo then create foo foo.bark else foo.bark end  would repeat the foo.bark and obviously I want to avoid it... and even the last statement won't compile with void-safety as foo on else could be void... • Jan 24 Eiffel: a way to ensure db_cursor: DB_RESULT has not moved I'm looking for a way to ensure that cursor: detachable DB_RESULT from DB_SELECTION class hasn't moved. I didn't find any method to get access to it. Does the following statement ensure it?  ensure cursor_not_moved: a_db_service.cursor.is_equal(old a_db_service.cursor)  The item method for example doesn't seem to ensure that even if it is only consulting a value of a given row index • Jan 13 Eiffel: Error: variable is not properly set. in make calling default_create or any parent calling/redefining default_create Not sure exactly, but it makes various time I got a Error: variable is not properly set. in creation procedures' calling order. I figured out that creating class attributes before calling default_create seemed to solve the problem. Why is that so? It doesn't seem that default_create calls something in my make routine??!!! Try to make an example even if I don't think I can reproduce it with a simple example... ## Working class A feature attr: B make do create attr default_create end end  ## Error: variable is not properly set. class A feature attr: B make do default_create create attr end end  • Jan 13 Eiffel: change the signature of a inherited feature How is the correct way to change the signature of a feature in Eiffel if any? if there is no option as I understood, how would be the correct way to define in a parent class that there will be a feature to be able to select but still don't know arguments number and types (types are resolvable with polymorphism...) Is the only available playing with polymorphism having an argument into class a to select of type ANY? ## class SELECTABLE class SELECTABLE select deferred end end -- class  ## class DB_SERVICE class DB_SERVICE inherit SELECTABLE (...) feature -- Status setting select (a_db_connection: DB_CONNECTION) local l_qry: STRING do item := first_item_from_qry (l_qry) end end -- class  • Jan 11 Eiffel: Error: type is based on unknown class Trying to implement some test cases on EWF application with rest web services and JSON objects, I'm gettint a Error: type is based on unknown class. after adding my first class inheriting from EQA_TEST_SET Seems pretty complicated to implement test cases for a simple curl -v --header "Content-Type: application/json" --request POST --data '{"id":11,"name":"someName","enumerate":{"id":5}}' http://localhost:9997/someEntity curl command! How can I do that? Where is there some example? I'm trying to copy-paste the example from $ISE_LIBRARY/contrib/library/web/framework/ewf/wsf/tests/src/test_wsf_request.e as a base, but for the moment....

I can find the class when browsing the dependencies as shown in screenshot, but the compiler not! strange behaviour!

## My app_ewf_app.ecf

<?xml version="1.0" encoding="ISO-8859-1"?>
<system xmlns="http://www.eiffel.com/developers/xml/configuration-1-19-0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.eiffel.com/developers/xml/configuration-1-19-0 http://www.eiffel.com/developers/xml/configuration-1-19-0.xsd" name="sit_ewf_app" uuid="0AB55F0B-014A-4775-B93F-ACC31C9300D5">
<target name="common" abstract="true">
<file_rule>
<exclude>/CVS$</exclude> <exclude>/EIFGENs$</exclude>
<exclude>/\.svn$</exclude> </file_rule> <option warning="true"> <assertions precondition="true" postcondition="true" check="true" invariant="true" loop="true" supplier_precondition="true"/> </option> <capability> <catcall_detection support="none"/> <concurrency support="scoop"/> <void_safety support="all" use="all"/> </capability> <library name="base" location="$ISE_LIBRARY\library\base\base-safe.ecf"/>
<library name="http" location="$ISE_LIBRARY\contrib\library\network\protocol\http\http-safe.ecf"/> <library name="json" location="$ISE_LIBRARY\contrib\library\text\parser\json\library\json.ecf"/>
<library name="lexical" location="$ISE_LIBRARY\contrib\library\gobo\library\lexical\library.ecf"/> <library name="logging" location="$ISE_LIBRARY\library\runtime\logging\logging.ecf"/>
<library name="odbc" location="$ISE_LIBRARY\library\store\dbms\rdbms\odbc\odbc.ecf"/> <library name="store" location="$ISE_LIBRARY\library\store\store.ecf"/>
<library name="time" location="$ISE_LIBRARY\library\time\time.ecf"/> <library name="wsf" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\wsf-safe.ecf"/>
<library name="wsf_extension" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\wsf_extension.ecf"/> <cluster name="database" location=".\database\" recursive="true"/> <cluster name="entity" location=".\entity\" recursive="true"/> <cluster name="error" location=".\error\" recursive="true"/> <cluster name="handler" location=".\handler\" recursive="true"/> <cluster name="logger" location=".\logger\" recursive="true"/> <cluster name="misc" location=".\misc\" recursive="true"/> <cluster name="relationship" location=".\relationship\" recursive="true"/> <cluster name="rest" location=".\rest\" recursive="true"/> <cluster name="service" location=".\service\" recursive="true"/> <cluster name="sit-json" location=".\sit-json\" recursive="true"/> <!-- TESTS --> <cluster name="tests" location=".\tests\" recursive="true"/> </target> <target name="ewf_app_any" extends="common"> <root class="EWF_APP" feature="make_and_launch"/> <capability> <concurrency support="scoop"/> </capability> <library name="cgi" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\connector\cgi-safe.ecf"/>
<library name="libfcgi" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\connector\libfcgi-safe.ecf"/> <library name="standalone" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\connector\standalone-safe.ecf"/>
<cluster name="launcher" location=".\launcher\">
<cluster name="any_launcher" location="$|any\"/> </cluster> <cluster name="src" location=".\src\" recursive="true"/> </target> <target name="ewf_app_standalone" extends="common"> <root class="EWF_APP" feature="make_and_launch"/> <capability> <catcall_detection support="none"/> <concurrency support="scoop"/> <void_safety support="all"/> </capability> <variable name="httpd_ssl_disabled" value="true"/> <library name="default_standalone" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\default\standalone-safe.ecf"/>
<library name="eel" location="$ISE_LIBRARY\contrib\library\text\encryption\eel\eel.ecf"/> <library name="ewsgi" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\ewsgi\ewsgi.ecf"/>
<library name="http_client" location="$ISE_LIBRARY\contrib\library\network\http_client\http_client.ecf"/> <library name="testing" location="$ISE_LIBRARY\library\testing\testing-safe.ecf"/>
<cluster name="launcher" location=".\launcher\">
<cluster name="default_launcher" location="$|default\"/> </cluster> <cluster name="src" location=".\src\" recursive="true"/> </target> <target name="ewf_app_cgi" extends="common"> <root class="EWF_APP" feature="make_and_launch"/> <capability> <concurrency support="scoop" use="none"/> </capability> <library name="default_cgi" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\default\cgi-safe.ecf"/>
<cluster name="launcher" location=".\launcher\">
<cluster name="default_launcher" location="$|default\"/> </cluster> <cluster name="src" location=".\src\" recursive="true"/> </target> <target name="ewf_app_libfcgi" extends="common"> <root class="EWF_APP" feature="make_and_launch"/> <capability> <concurrency support="scoop" use="none"/> </capability> <library name="default_libfcgi" location="$ISE_LIBRARY\contrib\library\web\framework\ewf\wsf\default\libfcgi-safe.ecf"/>
<cluster name="launcher" location=".\launcher\">
<cluster name="default_launcher" location="\$|default\"/>
</cluster>
<cluster name="src" location=".\src\" recursive="true"/>
</target>
<target name="ewf_app" extends="ewf_app_any">
</target>
</system>


## My error

• Jan 11
Eiffel: unknown identifier cursor on LINKED_LIST[STRING]

I have an unknown identifier on the local like some_values.cursor, I really don't understand why!

qry_update_set_fields (some_keys, some_values, some_unstored_field_names: LINKED_LIST[STRING]): STRING
require
same_some_keys_some_values_count: some_keys.count = some_values.count
local
l_val_c: like some_values.new_cursor
do
Result := ""
l_val_c := some_values.new_cursor
across
some_keys as l_key_c
loop
Result := l_key_c.item + "=" + l_val_c.item + ","
l_val_c.forth
end
if Result.ends_with (",") then
Result.remove_tail (1)
end
ensure
dont_modify_parameters: old some_keys.is_equal (some_keys) and old some_values.is_equal (some_values)
end


## working

l_val_c: LINKED_LIST_CURSOR [STRING]


## Neither working

l_val_c: LINKED_LIST_CURSOR [like some_values.item]

• Jan 11
Eiffel: Call use obsolete feature. Call to feature to_string_8': Use name_32' instead

I have a warning I cannot get rid of neither understand:

Eiffel: Call use obsolete feature. Call to feature to_string_8': Use 'name_32' instead

item_prototype is a DB_SERVICE where I redefine out

if attached {APP_CONFIGURATION}.application_instance.selected_entity_primary_key ({SIT_UTIL}.class_name_lowercase ({like item_prototype})) as l_pk then


One more point is that I wasn't able to copy the warning msg to my clipboard, how do I do that? if there is a way into EiffelStudio.

• 2018, Dec 26
Eiffel Web Framework, app run on linux raises Address already in use: IO_FAILURE raised

After stopping an EWF app and starting it again in a Address already in use: c_bind Address already in use: IO_FAILURE raised

As explained here, it seems that TCP socket timeout is not available for some time before being released by OS.

• 2018, Dec 20
Eiffel library: JSON_OBJECT.item and common method to get content

If I want to have the content value as string of a JSON_OBJECT.item ("key") without having to

some_json_value_as_string: STRING
do
if attached {JSON_STRING} l_json_o as l_s then
Result := l_s.unescaped_string_8
elseif attached {JSON_NUMBER} l_json_o as l_n then
Result := l_n.item.out
else
check
you_forgot_to_treat_a_case: False
end
end
end


for a json object like

{
|       |       "datasource_name": "DODBC",
|       |       "ewf_listening_port": 9997,
|       |       "log_file_path": "/var/log/ewf_app.log",
|       |       "default_selected_company": 1,
|       |       "default_selected_branch": 1,
|       |       "default_selected_consumption_sector": 1,
|       |       "default_selected_measuring_point": 1,
|       |       "default_selected_charge_unit": -1
|       }


the {JSON_VALUE}.representation with io.putstring is:

datasource_username=dev_db_usr


and not the value only!!!

is there a way to do that? I didn't find intuitive the different methods of JSON_VALUE: values as the out method gives the class and pointer address, which is really far from a string representation of the associated json object for me...

• 2018, Dec 20
How do I initialize and fill a linked list in Eiffel?

Here's what I have so far.

create {LINKED_LIST[INTEGER]} list.make
from
i := 0
list.start
until
i = 11
loop
list.put(i)
i := i + 1
list.forth
end


The debugger points to line list.put(i). I think the problem is that list is not properly initialized? I'm having a bit of an issue with figuring out how to use linked_list because I can't find any proper tutorial to help with. As you can see, I am just trying to write a LINKED_LIST program that adds numbers [0,10] in a linked list. Not a school project. Just practicing ahead of an upcoming course. Please help!

• 2018, Dec 17
Eiffel: How do I handle timezones?

I didn't find any notion of timezone DATE_TIME class and TIME class. Am I wrong?

How do I handle timezones with Eiffel library?

Is there a way to specify it from the {DATE_TIME}.formated_out ("YYYY-MM-DD [0]hh:[0]mi:[0]ss")

Is there a setter for timezone?

I already got this problem with the logger which is logging with UTC...

The only workaround I found was l.hour_add (-3) before the formated_out which is really dirty

• 2018, Dec 17
How to check if file exists in Eiffel
feature

open_file_sample
local
l_file: UNIX_FILE_INFO
l_path: STRING
do
make
l_path := "/var/log/syslog"
l_file.update (l_path)
if l_file.parent_directory.exists and then l_file.parent_directory.is_writtable then
create l_file.make
end
-- AS the above statement doesn't exist!
check
end
end


Is this the proper way to check for file existence in Eiffel?

I was wondering if there is a way not to create 2 objects. I'll complete my check with following statement:

• define path l_file_path := "/some/path/with_file.log"
• check if parent directory exists and has rights to write into
• create log file
• 2018, Dec 13
Eiffel compilation through Makefile and dpkg-buildpackage -us -uc generating an error
• 2018, Dec 10
How to use CURSOR_TREE class in Eiffel?

Does this work for removing first two children from a node?

remove_children(current_node : CURSOR_TREE[EXPRESSION])
do
current_node.down (1)
current_node.remove
current_node.forth
current_node.remove
end
`

Or does that only remove the current_node?

• See more ...