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install Doom Emacs + Clojure

install apt install

• install clojure
• instal rlwrap
• install emacs 29.1
• optional install lazydocker
• install emacs-doom from https://github.com/doomemacs/doomemacs#install

But before you doom yourself, here are some things you should know:

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package com.my.helpers

import io.github.serpro69.kfaker.faker
import mu.KLogging
import org.apache.avro.SchemaBuilder
import org.apache.avro.generic.GenericData
import org.apache.avro.generic.GenericRecord
import org.apache.avro.reflect.ReflectData
import org.apache.parquet.avro.AvroParquetWriter
import org.apache.parquet.hadoop.ParquetFileReader

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import java.util.Arrays;
import reactor.core.publisher.Flux;
import reactor.core.scheduler.Schedulers;

Flux.fromIterable(Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20))
        .groupBy(x -> x.hashCode() % 5)
        .parallel(10)
        .runOn(Schedulers.parallel())
        .flatMap(g -> g.collectMap(y -> {log.info(" g: "+g.key()+" y: "+ y); return y;}).log("subscr"))
        .subscribe();

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data-modeling

docker run --name scyllaU -d scylladb/scylla:3.0.10
docker exec -it scyllaU nodetool status
docker exec -it scyllaU cqlsh

CREATE KEYSPACE Pets_Clinic WITH replication = {'class': 'SimpleStrategy', 'replication_factor' : 1};
use Pets_Clinic; 

CREATE TABLE heartrate_v1 (

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interface DaoOperationsSyntax {
  val dao: DaoDatabase

  fun User.queryUser() = 
    dao.query("SELECT * from Users where userId = ${this.id}")

  fun Company.queryCompany() = 
    dao.query("SELECT * from Companies where companyId = ${this.id}")
}

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Latency Comparison Numbers
--------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

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import akka.actor.{ActorSystem, Props}
import akka.stream.{ActorMaterializer, OverflowStrategy}
import akka.stream.scaladsl.{Flow, Sink, Source}
import com.typesafe.config.ConfigFactory
import jetbrains.exodus.entitystore.{PersistentEntityStoreImpl, PersistentEntityStores}
import jetbrains.exodus.env.{Environments, Store}
import org.apache.commons.lang3.SerializationUtils

import collection.JavaConverters._

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/*  "org.jetbrains.xodus" % "xodus-openAPI" % "1.2.3",
    "org.jetbrains.xodus" % "xodus-entity-store" % "1.2.3",
*/
object XodusApp extends App {

  import jetbrains.exodus.bindings.StringBinding.{entryToString, stringToEntry}
  import jetbrains.exodus.env.StoreConfig.WITHOUT_DUPLICATES

  val env = Environments.newInstance("data")

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/* library dependecies
   "org.xerial" % "sqlite-jdbc" % "3.23.1",
   "org.tpolecat" %% "doobie-core"      % "0.5.3",
   "org.tpolecat" %% "doobie-hikari"    % "0.5.3", // HikariCP transactor.
   "org.tpolecat" %% "doobie-specs2"    % "0.5.3", // Specs2 support for typechecking statements.
   "org.tpolecat" %% "doobie-scalatest" % "0.5.3",  // ScalaTest support for typechecking statements.
*/
object TryDoobie extends App {

  import doobie._

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#!/bin/sh
#http://www.thegeekstuff.com/2011/01/advanced-regular-expressions-in-grep-command-with-10-examples-%E2%80%93-part-ii/


# GENERAL
# print lines begining with range of letters
grep ^[A-D] table.txt


# REGEX