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What is function overloading and overriding in php?

...that method. In PHP, you can only overload methods using the magic method __call. An example of overriding: <?php class Foo { function myFoo() { return "Foo"; } } class Bar extends Foo { function myFoo() { return "Bar"; } } $foo = new Foo; $bar = new Bar; echo($foo-&...
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How do I check if a string is valid JSON in Python?

...on script returns a boolean if a string is valid json: import json def is_json(myjson): try: json_object = json.loads(myjson) except ValueError as e: return False return True Which prints: print is_json("{}") #prints True print is_json("{asdf}") ...
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What is __init__.py for?

What is __init__.py for in a Python source directory? 12 Answers 12 ...
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Undefined reference to `pow' and `floor'

... You can also use LD_PRELOAD to tell ld runtime linker to include libm.so in the memory map and symbol table of the process, so these symbols get loaded and everything works as expected – debuti May 28 '18 ...
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How to rename with prefix/suffix?

...ly be short and simple for this. For example, to rename all *.jpg to prefix_*.jpg in the current directory: for filename in *.jpg; do mv "$filename" "prefix_$filename"; done; share | improve this ...
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How to fix “Attempted relative import in non-package” even with __init__.py

... Yes. You're not using it as a package. python -m pkg.tests.core_test share | improve this answer | follow | ...
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Hash function that produces short hashes?

...ike the accepted answer): import base64 import hashlib import uuid unique_id = uuid.uuid4() # unique_id = UUID('8da617a7-0bd6-4cce-ae49-5d31f2a5a35f') hash = hashlib.sha1(str(unique_id).encode("UTF-8")) # hash.hexdigest() = '882efb0f24a03938e5898aa6b69df2038a2c3f0e' result = base64.b64encode(has...
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detach all packages while working in R

...h()[pos]’. This can be an unquoted name or a character string but _not_ a character vector. If a number is supplied this is taken as ‘pos’. So we need to repeatedly call detach() once per element of pkg. There are a couple of other arguments we need to specify to get thi...
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Where is my Django installation?

...go <module 'django' from '/usr/local/lib/python2.6/dist-packages/django/__init__.pyc'> share | improve this answer | follow | ...
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ElasticSearch: Unassigned Shards, how to fix?

...enable shard allocation. # v0.90.x and earlier curl -XPUT 'localhost:9200/_settings' -d '{ "index.routing.allocation.disable_allocation": false }' # v1.0+ curl -XPUT 'localhost:9200/_cluster/settings' -d '{ "transient" : { "cluster.routing.allocation.enable" : "all" } }' Elas...