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Questions tagged [symbols]

can refer to a letter or special character; a primitive data type in many programming languages; an item of the alphabet of a formal language.

Symbol can refer to:

  • A letter or special character, e.g. '@'. Questions about character processing or dealing with specific characters can be tagged with this tag.
  • A primitive data type in many programming languages (Lisp, Prolog, Ruby, Smalltalk etc.)
  • An item of the alphabet of a formal language.
3495 questions
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What's the difference between a string and a symbol in Ruby?

What's the difference between a string and a symbol in Ruby and when should I use one over the other?
readonly
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11 answers

Missing symbol names when profiling IPhone application with Instruments

I am compiling an iPhone application via command line (so no Xcode options involved) however I am unable to get my symbol names to show when profiling with Instruments. I have tried several flags such as -gdawrf-2 and -g without any success. I have…
Mac Twist
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Rails load YAML to hash and reference by symbol

I am loading a YAML file in Rails 3.0.9 like this: APP_CONFIG = YAML.load(File.read(File.expand_path('../app.yml', __FILE__))) It loads the all of the contents like hierarchical hashes, no problem. The part I don't like is the fact that the hashes…
Michael K Madison
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3 answers

Purpose of Scala's Symbol?

Possible Duplicate: What are some example use cases for symbol literals in Scala? What's the purpose of Symbol and why does it deserve some special literal syntax e. g. 'FooSymbol?
soc
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5 answers

readelf-like tool for Mac OS X?

Is there a tool for reading Mac OS X binaries that would print information about relocation tables and symbol offsets similar to this readelf output? readelf -r app Relocation section '.rel.dyn' at offset 0x5ec contains 2 entries: Offset Info …
karlphillip
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5 answers

Why is it not a good idea to dynamically create a lot of symbols in ruby (for versions before 2.2)?

What is the function of symbol in ruby? what's difference between string and symbol? Why is it not a good idea to dynamically create a lot of symbols?
Ikbear
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4 answers

What does a double colon followed by an equals sign (::=) mean in programming documentation?

What does ::= mean in programming documentation? For example in the Lua documentation: or in Python documentation.
Charles Holbrow
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68
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2 answers

What does the Ruby method 'to_sym' do?

What does the to_sym method do? What is it used for?
keruilin
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5 answers

What does the SQL # symbol mean and how is it used?

Can someone please explain to me what the # symbol means in MS SQL Code. I've tried Googling it, and even searching on StackOverflow, but can't seem to find the answer. I feel like an idiot - having one of "those" days. Please help.
Saajid Ismail
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4 answers

What Unicode symbol represents a person?

Does there exist a Unicode symbol that represents a person? I would expect something like this: I need a short way to represent a price per person, such as “25€/person”, but with the word “person” replaced with a Unicode character for a person. The…
jbaylina
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4 answers

What are the meanings of the columns of the symbol table displayed by readelf?

Could someone explain the columns shown of the symbol table using readelf?
Swaroop S
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8 answers

Duplicate symbol issues

During a refactor of an iOS project, I ran into this bear of a bug. During the linking phase, I get this message: ld: duplicate symbol _OBJC_IVAR_$_TinCanViewController.currentViewController in /path/to/TinCanViewController-E98A666B7AF2673A.o and…
drewww
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1 answer

Undefined Symbols for architecture x86_64: Compiling problems

So I am trying to start an assignment, my professor gives us a Main.cpp, Main.h, Scanner.cpp, Scanner.h, and some other utilities. My job is to create a Similarity class to compare documents using the cosine and Jaccard coefficients. However, I can…
Trevor Hutto
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4 answers

What does to_proc method mean in Ruby?

I am learning rails and following this thread. I am stuck with the to_proc method. I consider symbols only as alternatives to strings (they are like strings but cheaper in terms of memory). If there is anything else I am missing for symbols, then…
swapnesh
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Practical examples of using symbols in Scala?

Scala has symbols - names that start with a single quote ' and which are a kind of string constants. I know symbols from Ruby (where they start with a colon). In Ruby they are used for some meta-programming tasks, like generating getters and setters…
Jesper
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