Logic Bullshit

logic.rb

# in logic notation
# a -> b is "if a then b"

# so in programming:

a = false
b = true

if a
    puts "a true"
    if b
        puts "b true"
    end
end

# since a == false, no output. essentially "if a" gets 
# executed and short circuits, no "then b". b is irrelevant

# in logic, the whole statement gets evaluated and truth isn't derived
# from the truth of the first evaluated term in a sequence, so

# a = false, b = true, if a then b = true
# a = false, b = false, if a then b = true
# a = true, b = true, if a then b = true
# a = true, b = false, if a then b = false

# "if a then b" is only false if a is true and b is false because the english 
# representation is like "it follows that if a then also b" so equally true is "if not a then still could be b"
# or "if not a then definitely not b" but never "if a then not b"

# which is easy enough to parse out of course but programming brain wants to be like
# "oh, not a? well fuck b who cares?"

# (a&b) follows what you'd expect for (a && b) i.e. both true or statement false
# (avb) follows (a || b) i.e. any true value makes it true

# BUT when you're used to using that short circuit logic to do things like
c = a || b 
# then you're only used to considering the first term's truthiness because the
# second term is taken as a value for assignment, so the truthiness of the full statement doesn't matter
# again, easy enough to parse but programming zug brain is like "a or b but only actually care about a"

# a <--> b is a whole other dumb thing because it's true only if both are true or both are false

# so it's all like JUST different enough to fuck you up