Ruby
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to check the path of the ruby
which ruby
/usr/bin/ruby
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If you executing ruby from shell script
go to vi mode ......and then type the programme and save it in .rb The file name should have extension of .rb and save it any where in !
vi trial.rb
#!/usr/bin/ruby
./trial.rb
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If you executing ruby from normal mode
vi trial.rb (assume that we save in desktop or file system )
ruby trial.rb (to compile the ruby code)
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comments in ruby
single line comment
#This is the single line comment in ruby
multiple line comment
==begin
to start with multiple line comment we have to start ==begin from beggining and ==end from ending
==end
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declaring variables in ruby
a=10
b=10
c=10
parallel way of assigning variables in ruby
a,b,c,d=10,20,30,45
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to know the what type of variables in ruby
a=25
b=45.0
c="welcome"
a.class()
b.class()
c.class()
to check whether it is integer/float/string
a.kind_of? Integer
b.kind_of? String
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converting variables values
y=20
y.to_s #it converts to string
y.to_f #it converts to float
to convert the integer binary
y.to_s(2) #converts to binary base 2
y.to_s(8) #converts to base 8 (octal)
y.to_s(16) #converts to base 16(Hexa decimal)
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variable scope in ruby
ruby has 5 types of variable scope in ruby
$ --global variable
@-- instance variable
a-z--local variable
A-Z-- constant variable
@@---class variable
to know the type of the variable in ruby
defined? ($x or @x or x or @@x)
