strings/written_formats.rb

tests/_examples/strings/written_formats.rb in the metorex repository.

# `sprintf` writes a value the way a directive names: a base, a fraction, a
# character, or the text a value stands for.
p sprintf("%b %o %x %X", 10, 87, 196, 196)
p sprintf("%d %i %u", 112, 112, 112)
p sprintf("%e %E %f", 109.52, 109.52, 10.952)
p sprintf("%g %G", 0.0000123456, 1234567)
p sprintf("%a %A", 196, 196)
p sprintf("%c %p %s", 97, [1], "abc")

# A negative number written in a base of its own carries a run of the base's
# largest digit reaching back forever.
p sprintf("%b %o %x %X", -10, -87, -196, -196)
p sprintf("%010b %.7b", -10, -5)

# A sign, a width, a precision, and the `#` that writes the base out.
p sprintf("%+d % d %-6d| %06d", 5, 5, 5, 5)
p sprintf("%#b %#o %#x %#X", 10, 87, 196, 196)
p sprintf("%.3s %6.2f %*d", "hello", 3.14159, 6, 42)

# A directive can name which value it takes and read a width from another.
p sprintf("%2$s %1$s", "world", "hello")
p sprintf("%1$*2$d", 42, 8)

# A name reads its value from a Hash instead of from a position.
p sprintf("%<count>05d and %{label}", count: 42, label: "rest")

# Infinity and NaN are named rather than written out.
p sprintf("%f %e %g", Float::INFINITY, -Float::INFINITY, Float::NAN)

Output:

"1010 127 c4 C4"
"112 112 112"
"1.095200e+02 1.095200E+02 10.952000"
"1.23456e-05 1.23457E+06"
"0x1.88p+7 0X1.88P+7"
"a [1] abc"
"..10110 ..7651 ..f3c ..F3C"
"..11110110 ..11011"
"+5  5 5     | 000005"
"0b1010 0127 0xc4 0XC4"
"hel   3.14     42"
"hello world"
"      42"
"00042 and rest"
"Inf -Inf NaN"