# FLP-GSP
General Search Parser
# General Search String (GSS) Builder
[Goto the page](https://hakukano.github.io).
# General Search String (GSS) LALR(1) Grammar
```
Search -> Statements
Statements ->
-> Statements Relation
Relation -> GroupStart Comparison GroupEnd
-> GroupStart Relation And Relation GroupEnd
-> GroupStart Relation And Comparison GroupEnd
-> GroupStart Comparison And Relation GroupEnd
-> GroupStart Comparison And Comparison GroupEnd
-> GroupStart Relation Or Relation GroupEnd
-> GroupStart Relation Or Comparison GroupEnd
-> GroupStart Comparison Or Relation GroupEnd
-> GroupStart Comparison Or Comparison GroupEnd
-> GroupStart Not Relation GroupEnd
-> GroupStart Not Comparison GroupEnd
Comparison -> Str Equal Str
-> Str EqualCI Str
-> Str Greater Str
-> Str Less Str
-> Str Wildcard Str
-> Str Regex Str
-> Str In Array
-> Str IsNone
Str -> `[^`]*`
Array -> \[[^\[,]*\w*(,[^\[,]*)*\]
GroupStart -> (
GroupEnd -> )
And -> &
Or -> |
Not -> !
Equal -> =
EqualCI -> ~
Greater -> >
Less -> <
Wildcard -> *
Regex -> $
In -> ?
IsNone -> -
```
# Interpreter
Some example interpreters that maybe useful
## Evaluate
Customizable in-code evaluating interpreter. [Goto the file](https://github.com/Hakukano/FLP-GSP/blob/main/src/interpreter/evaluate.rs).
An example could be found [here](https://github.com/Hakukano/FLP-GSP/blob/main/tests/evaluate.rs).
### Concept
To evaluate a `Search`, you will need `EvaluateRules` and `EvaluatePairs`.
* `EvaluateRules`: You can overwrite any default rules for comparison. Usually, you may want to overwrite `is_greater_than` and `is_less_than` if the key has a numeric value. Rules should be reused as often as possible in order to reduce redundant codes.
* `EvaluatePairs`: Actual key-value pairs for the evaluation. You need to parse your values into strings so that rules can be applied.
## Mysql
Generating Mysql condition clause. [Goto the file](https://github.com/Hakukano/FLP-GSP/blob/main/src/interpreter/mysql.rs).
An example could be found [here](https://github.com/Hakukano/FLP-GSP/blob/main/tests/mysql.rs).
### Concept
To generate Mysql condition clause from a `Search`, you will need `MysqlRenames` and `MysqlTypes`.
* `MysqlRenames`: You can insert any rename rules to it. E.g. key `sex` in search string may need to be renamed to `table_a.gender` regarding the actual query string. All keys without rename rules will stay as is.
* `MysqlTypes`: You can insert any types to it. You need this because the condition clause is a prepare clause (i.e. all values are replaced as placeholder(?)) and you will be given a Vec<MysqlType> with search targets in the order that "?"s appear in the clause. For details, please read the example. Additionally, MysqlType::StringLike(String) is the default type if you didn't insert types for one or some keys.
## Postgres
Very similar to Mysql except for some types.