[jira] [Updated] (GROOVY-9806) [GEP] Create a LINQ-like DSL (advanced cases)

["Daniel Sun (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/GROOVY-9806?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Daniel Sun updated GROOVY-9806:
-------------------------------
    Description: 
_(See GROOVY-8258)_

h3. 9. WITH-Clause
h4. 9.1
{code:java}
with v as (
    from m in numbers
    where m <= 5
    select m
)
from n in v
limit 2, 5
select n
{code}
h3. 10. Union
h4. 10.1
{code:java}
from n in numbers1
select n
unionall
from n in numbers2
select n
{code}
h4. 10.2
{code:java}
from n in numbers1
select n
union
from n in numbers2
select n
{code}

  was:
h2. *Ⅰ. Introduction*

GINQ DSL is an alternative solution of GINQ, it is a simplified version of GINQ(GROOVY-9159) and will be implemented as a module "groovy-ginq".

GINQ DSL is wrapped with:
{code:java}
GINQ {
   // GINQ code
}
{code}
*NOTE:* The simplest GINQ should consists of {{from}} and {{select}}, which looks like:
{code:java}
from n in [1, 2, 3]
select n
{code}
h2. *Ⅱ. Sample code related to GROOVY-9159*
h3. 1. Filtering
h4. 1.1
{code:java}
from p in persons
where p.age > 15 && p.age <= 35
select p.name
{code}
h4. 1.2
{code:java}
from p in persons
where p.age > 15 && p.age <= 35
select p
{code}
h4. 1.3
{code:java}
from t in numbers 
where t <= 2
select t
{code}
h3. 2. Joining
h4. 2.1
{code:java}
from p in persons
innerjoin c in cities on p.city.name == c.name // putting `on` clause in the same line with `innerjoin` is recommended code style
select p.name, c.name
{code}
h4. 2.2
{code:java}
from p in persons
innerjoin c in cities on p.city == c
select p.name
{code}
h4. 2.3
{code:java}
from p in persons
leftjoin c in cities on p.city.name == c.name //  same with left outer join
select p.name, c.name
{code}
h4. 2.4
{code:java}
from p in persons
rightjoin c in cities on p.city.name == c.name //  same with right outer join
select p.name, c.name
{code}
h3. 3. Projection
h4. 3.1
{code:java}
from p in persons
select p.name
{code}
h4. 3.2
{code:java}
from p in persons
select p.name, p.age
{code}
h4. 3.3
{code:java}
from p in persons
select [name: p.name, age: p.age]
{code}
h4. 3.4
{code:java}
from p in persons
select new Person(name: p.name, age: p.age)
{code}
h4. 3.5
{code:java}
from p in persons
select p
{code}
h3. 4. Grouping
h4. 4.1
{code:java}
from p in persons
groupby p.gender
select p.gender, max(p.age)
{code}
h3. 5. Having
h4. 5.1
{code:java}
from p in persons
groupby p.gender
having p.gender == 'Male'
select p.gender, max(p.age)
{code}
h3. 6. Sorting
h4. 6.1
{code:java}
from p in persons
orderby p.age
select p.name
{code}
h4. 6.2
{code:java}
from p in persons
orderby p.age in desc // "`in` order" means sorting
select p.name
{code}
h4. 6.3
{code:java}
from p in persons
orderby p.age in desc, p.name in asc // asc is optional
select p.name
{code}
h3. 7. Pagination
h4. 7.1
{code:java}
from n in numbers
limit 2, 5
select n
{code}
h4. 7.2
{code:java}
from n in numbers
limit 5
select n
{code}
h3. 8. Nested Queries
h4. 8.1
{code:java}
from v in (
    from n in numbers
    where n <= 5
    select n
)
limit 2, 5
select v
{code}
h3. 9. WITH-Clause
h4. 9.1
{code:java}
with v as (
    from m in numbers
    where m <= 5
    select m
)
from n in v
limit 2, 5
select n
{code}
h3. 10. Union
h4. 10.1
{code:java}
from n in numbers1
select n
unionall
from n in numbers2
select n
{code}
h4. 10.2
{code:java}
from n in numbers1
select n
union
from n in numbers2
select n
{code}


> [GEP] Create a LINQ-like DSL (advanced cases)
> ---------------------------------------------
>
>                 Key: GROOVY-9806
>                 URL: https://issues.apache.org/jira/browse/GROOVY-9806
>             Project: Groovy
>          Issue Type: New Feature
>            Reporter: Daniel Sun
>            Assignee: Daniel Sun
>            Priority: Major
>             Fix For: 4.0.0-alpha-2
>
>
> _(See GROOVY-8258)_
> h3. 9. WITH-Clause
> h4. 9.1
> {code:java}
> with v as (
>     from m in numbers
>     where m <= 5
>     select m
> )
> from n in v
> limit 2, 5
> select n
> {code}
> h3. 10. Union
> h4. 10.1
> {code:java}
> from n in numbers1
> select n
> unionall
> from n in numbers2
> select n
> {code}
> h4. 10.2
> {code:java}
> from n in numbers1
> select n
> union
> from n in numbers2
> select n
> {code}



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