dhermes

Came up in hardfinhq/go-date#13

Consider

package main

import (
	"fmt"
	"os"

dhermes

/1930s.html
/1960s.html
/1970s.html
/1980s.html
/1990s.html
/2000s.html
/2010s.html

dhermes

import graphql.language
import networkx as nx
import tabulate


def _find_field_fragment_dependencies(
    field_node: graphql.language.ast.FieldNode,
) -> list[str]:
    if field_node.selection_set is None:
        return []

dhermes

Subtleties of Go JSON marshaling and null / nil

The TL;DR here is that if the standard encoding/json machinery in Go sees a null in a JSON field or a nil pointer in a Go field (of type *T), then it will not invoke the UnmarshalJSON() / MarshalJSON() on your type.

$ go run ./main.go
t1 = main.T{Shift:(*main.Point)(nil)} (nil stays nil, UnmarshalJSON() not invoked)

dhermes

# Copyright (c) 2023 - Present. Hardfin, Inc. All rights reserved.
# Hardfin Confidential - Restricted

import csv
import io
import pathlib
import subprocess
import tempfile

dhermes

The problem with "as-of-now" computed columns

The below illustrates why only actually IMMUTABLE functions should be used for PostgreSQL generated columns.

Basic status

Using a function that incorporates the current time, we can generate a status based on the value of a given timestamp:

dhermes

dhermes

How many nan values exist?

It turns out a lot (2**52). Anything where the 12 exponent bits are all 1, independent of the values of the other 52 bits).

$ python main.py
binary(1.0)  = 0011111111110000000000000000000000000000000000000000000000000000
binary(2.0)  = 0100000000000000000000000000000000000000000000000000000000000000
binary(-1.0) = 1011111111110000000000000000000000000000000000000000000000000000

dhermes

package main

import (
	"fmt"
	"os"

	"github.com/google/uuid"
)

type mapKey struct {

dhermes

/__pycache__/
/supervisord.log
/supervisord.pid