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let cache = new Map();
let pending = new Map();

function fetchTextSync(url) {
  if (cache.has(url)) {
    return cache.get(url);
  }
  if (pending.has(url)) {
    throw pending.get(url);
  }

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            const { x: offsetLeft } = currentTarget.getBoundingClientRect();
            const innerWidth = window.innerWidth;
            const offsetRight = innerWidth - offsetLeft;
            if (offsetLeft < TOOLTIP_WIDTH / 2) {
                // if left space is too small
                //  --------
                //  |s.    |
                //  |----  | s = offsetLeft
                //  |      | left = -s = -
                //  --------

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const alphas = {
  a: 101,
  b: 2,
  c: 3,
  d: 5,
  e: 7,
  f: 11,
  g: 13,
 h: 17,

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when do migrations, if want make Backward Compatibility, you can add the new function above the old one

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#!/bin/bash

set -e

curl -L -O http://geolite.maxmind.com/download/geoip/database/GeoLite2-Country-CSV.zip
unzip GeoLite2-Country-CSV.zip
rm GeoLite2-Country-CSV.zip

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telnet exampledomain.com 25
Trying 1.1.1.1...
Connected to exampledomain.com (1.1.1.1).
Escape character is '^]'.
220-server1.exampledomain.com ESMTP Exim 4.66 #1 Wed, 01 Jua 2020 23:55:12 +0200
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
EHLO exampledomain.com
250-server1.exampledomain.com Hello  [1.1.1.2]
250-SIZE 52428800

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__dirname

```
_, filename, _, ok := runtime.Caller(0)
if !ok {
    panic("No caller information")
}
__dirname := path.Dir(filename)
```

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Installing Postgres via Brew

Pre-Reqs

Brew Package Manager

In your command-line run the following commands:

1. brew doctor
2. brew update

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The error is

Building native extensions.  This could take a while...
ERROR:  Error installing libxml-ruby:
	ERROR: Failed to build gem native extension.

    current directory: /Users/<username>/.rbenv/versions/2.3.7/lib/ruby/gems/2.3.0/gems/libxml-ruby-3.1.0/ext/libxml
/Users/<username>/.rbenv/versions/2.3.7/bin/ruby -r ./siteconf20190523-40908-1mq6z0c.rb extconf.rb
checking for libxml/xmlversion.h in /opt/include/libxml2,/opt/local/include/libxml2,/usr/local/include/libxml2,/usr/include/libxml2... no
*** extconf.rb failed ***

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The idea of *shunting yard algorithm* is to keep operators on a stack until their operands have been parsed. The operands are
kept on a second stack. The *shunting yard algorithm* can be used to directly evaluate expressions as they are parsed, to create
a reverse Polish notation of an infix expression, or to create an AST. I'll create an AST, so my operand stacks will contain trees

The key to the algorithm is to keep the operators on the operator stack odered by precedence(lowest at bottom and highest at the top)
at least in the absence of parenthese. Before pushing an operator onto the operator stack, all higher precedence operators are cleard
from the stack. Clearing an operator consists of removing the operator from the operator stack and its operands from the operand stack
making a new tree, and pushing that tree onto the operand stack. At the end of an expression the remaining operators are put into
trees with their operands and that is that.