After writing tons of Java code that [checks a string variable for both null and equality to the empty string]
Not all implicit conversions introduce problems. Casting to a Boolean type, as the if statement does, is fine with the caveat that which values are considered "truthy" or "falsey" depends on the language. For example, PHP's ordinary bool cast rules are pretty much the same as Python's, except that the string "0" is falsey in PHP but truthy in Python. C and Java have their own definition: a nonzero primitive or a nonnull pointer is truthy. I find these implicit conversions, as well as some language-specific rule for implicit conversion to the language's string type, to make sense in general.
The practical problem with how PHP handles comparisons comes when it performs implicit conversions that make little sense. Strings more often than not end up converted to numbers before they're compared.
For the parse errors, you mean you don't do precommit hooks to do php -l to validate your checkins and don't have continuous integration setup?
You are correct that a lot of people do not. For one thing, they may lack the money to lease both a testing environment and a production environment from the hosting provider. Or they may lack access to server logs because the hosting provider doesn't provide server logs to customers on plans below the VPS tier.
For the undefined functions, if you're doing OOP, the language has had great support for autoloading classes for over a decade
Autoload failures caused fatal errors until 5.3, and some hosting providers were still on 5.2 after 5.4 came out.
The only valid complaint is that the major version isn't incremented often enough to clue people in that there are potential breaking problems.
True. But there are several cases in Python where the interpreter implements both sets of semantics and allows each source code file to select one or the other. Some, such as the division semantics, use the from __future__ statement; others, such as the parallel "classic classes" and "new classes" in the 2.x series, use other syntactic triggers. And unlike Python, where the initial #!/usr/bin/env line selects the interpreter version, the choice of PHP version depends on a server configuration that's often out of the hosting subscriber's control.
PHP is basically a thin wrapper for C libraries.
Thin wrappers are better when they're namespaced. Namespaces allow providing both traditional names and PEP 8-compliant names without overly polluting the global namespace.
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