Calling a Function From a String With the Function's Name in Ruby

141

How can I do what they are talking about here, but in Ruby?

How would you do the function on an object? and how would you do a global function (see jetxee's answer on the post mentioned)?

EXAMPLE CODE:

event_name = "load"



def load()

  puts "load() function was executed."

end



def row_changed()

  puts "row_changed() function was executed."

end 



#something here to see that event_name = "load" and run load()

UPDATE:
How do you get to the global methods? or my global functions?

I tried this additional line

puts methods

and load and row_change where not listed.

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

add a comment |

141

How can I do what they are talking about here, but in Ruby?

How would you do the function on an object? and how would you do a global function (see jetxee's answer on the post mentioned)?

EXAMPLE CODE:

event_name = "load"



def load()

  puts "load() function was executed."

end



def row_changed()

  puts "row_changed() function was executed."

end 



#something here to see that event_name = "load" and run load()

UPDATE:
How do you get to the global methods? or my global functions?

I tried this additional line

puts methods

and load and row_change where not listed.

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

add a comment |

141

How can I do what they are talking about here, but in Ruby?

How would you do the function on an object? and how would you do a global function (see jetxee's answer on the post mentioned)?

EXAMPLE CODE:

event_name = "load"



def load()

  puts "load() function was executed."

end



def row_changed()

  puts "row_changed() function was executed."

end 



#something here to see that event_name = "load" and run load()

UPDATE:
How do you get to the global methods? or my global functions?

I tried this additional line

puts methods

and load and row_change where not listed.

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

How can I do what they are talking about here, but in Ruby?

How would you do the function on an object? and how would you do a global function (see jetxee's answer on the post mentioned)?

EXAMPLE CODE:

event_name = "load"



def load()

  puts "load() function was executed."

end



def row_changed()

  puts "row_changed() function was executed."

end 



#something here to see that event_name = "load" and run load()

UPDATE:
How do you get to the global methods? or my global functions?

I tried this additional line

puts methods

and load and row_change where not listed.

ruby function metaprogramming

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

edited May 23 '17 at 12:03

Community♦

edited May 23 '17 at 12:03

Community♦

edited May 23 '17 at 12:03

Community♦

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

asked Sep 10 '09 at 20:10

BuddyJoe

28.6k91263437

add a comment |

4 Answers
4

active

oldest

votes

206

To call functions directly on an object

a = [2, 2, 3]

a.send("length")

# or

a.public_send("length")

which returns 3 as expected

or for a module function

FileUtils.send('pwd')

# or

FileUtils.public_send(:pwd)

and a locally defined method

def load()

    puts "load() function was executed."

end



send('load')

# or

public_send('load')

Documentation:

Object#public_send

Object#send

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

3

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

1

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

1

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

9

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

|
show 6 more comments

Use this:

> a = "my_string"

> meth = a.method("size")

> meth.call() # call the size method

=> 9

Simple, right?

As for the global, I think the Ruby way would be to search it using the methods method.

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

1

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

add a comment |

Three Ways: `send` / `call` / `eval` - and their Benchmarks

Typical invocation (for reference):

s= "hi man"

s.length #=> 6

Using `send`

s.send(:length) #=> 6

Using `call`

method_object = s.method(:length) 

p method_object.call #=> 6

Using `eval`

eval "s.length" #=> 6

Benchmarks

require "benchmark" 

test = "hi man" 

m = test.method(:length) 

n = 100000 

Benchmark.bmbm {|x| 

  x.report("call") { n.times { m.call } } 

  x.report("send") { n.times { test.send(:length) } } 

  x.report("eval") { n.times { eval "test.length" } } 

}

...as you can see, instantiating a method object is the fastest dynamic way in calling a method, also notice how slow using eval is.

#######################################

#####   The results

#######################################

#Rehearsal ----------------------------------------

#call   0.050000   0.020000   0.070000 (  0.077915)

#send   0.080000   0.000000   0.080000 (  0.086071)

#eval   0.360000   0.040000   0.400000 (  0.405647)

#------------------------------- total: 0.550000sec



#          user     system      total        real

#call   0.050000   0.020000   0.070000 (  0.072041)

#send   0.070000   0.000000   0.070000 (  0.077674)

#eval   0.370000   0.020000   0.390000 (  0.399442)

Credit goes to this blog post which elaborates a bit more on the three methods and also shows how to check if the methods exist.

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

add a comment |

Personally I would setup a hash to function references and then use the string as an index to the hash. You then call the function reference with it's parameters. This has the advantage of not allowing the wrong string to call something you don't want to call. The other way is to basically eval the string. Do not do this.

PS don't be lazy and actually type out your whole question, instead of linking to something.

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

add a comment |

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4 Answers
4

active

oldest

votes

4 Answers
4

active

oldest

votes

206

To call functions directly on an object

a = [2, 2, 3]

a.send("length")

# or

a.public_send("length")

which returns 3 as expected

or for a module function

FileUtils.send('pwd')

# or

FileUtils.public_send(:pwd)

and a locally defined method

def load()

    puts "load() function was executed."

end



send('load')

# or

public_send('load')

Documentation:

Object#public_send

Object#send

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

3

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

1

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

1

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

9

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

|
show 6 more comments

206

To call functions directly on an object

a = [2, 2, 3]

a.send("length")

# or

a.public_send("length")

which returns 3 as expected

or for a module function

FileUtils.send('pwd')

# or

FileUtils.public_send(:pwd)

and a locally defined method

def load()

    puts "load() function was executed."

end



send('load')

# or

public_send('load')

Documentation:

Object#public_send

Object#send

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

3

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

1

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

1

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

9

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

|
show 6 more comments

206

To call functions directly on an object

a = [2, 2, 3]

a.send("length")

# or

a.public_send("length")

which returns 3 as expected

or for a module function

FileUtils.send('pwd')

# or

FileUtils.public_send(:pwd)

and a locally defined method

def load()

    puts "load() function was executed."

end



send('load')

# or

public_send('load')

Documentation:

Object#public_send

Object#send

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

To call functions directly on an object

a = [2, 2, 3]

a.send("length")

# or

a.public_send("length")

which returns 3 as expected

or for a module function

FileUtils.send('pwd')

# or

FileUtils.public_send(:pwd)

and a locally defined method

def load()

    puts "load() function was executed."

end



send('load')

# or

public_send('load')

Documentation:

Object#public_send

Object#send

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

edited Nov 21 '18 at 21:35

mu is too short

352k58692667

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

answered Sep 10 '09 at 20:17

Colin Gravill

3,50311715

3

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

1

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

1

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

9

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

|
show 6 more comments

3

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

1

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

1

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

9

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

+1 That works. This may be a dumb follow up ... but how come I can't find the word send in the Ruby source at - C:rubylibruby1.8fileutils.rb? Thought I would find the send function in there.

– BuddyJoe
Sep 10 '09 at 21:15

I was curious to what it was doing under the hood.

– BuddyJoe
Sep 10 '09 at 21:15

It's defined on object - ruby-doc.org/core/classes/Object.html#M000332 I picked a random function for interest value.

– Colin Gravill
Sep 10 '09 at 21:44

Interesting because before I read your answer twice, and fully grok'd it I ran the FileUtils.send("load") and it ran my function. so if I understand this correctly by creating functions in "global" am I adding the methods onto the root object? or not?

– BuddyJoe
Sep 10 '09 at 21:50

Good on you for looking stuff up in the source! :)

– Colin Gravill
Sep 10 '09 at 21:50

|
show 6 more comments

Use this:

> a = "my_string"

> meth = a.method("size")

> meth.call() # call the size method

=> 9

Simple, right?

As for the global, I think the Ruby way would be to search it using the methods method.

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

1

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

add a comment |

Use this:

> a = "my_string"

> meth = a.method("size")

> meth.call() # call the size method

=> 9

Simple, right?

As for the global, I think the Ruby way would be to search it using the methods method.

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

1

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

add a comment |

Use this:

> a = "my_string"

> meth = a.method("size")

> meth.call() # call the size method

=> 9

Simple, right?

As for the global, I think the Ruby way would be to search it using the methods method.

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

Use this:

> a = "my_string"

> meth = a.method("size")

> meth.call() # call the size method

=> 9

Simple, right?

As for the global, I think the Ruby way would be to search it using the methods method.

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

answered Sep 10 '09 at 20:18

Geo

46.2k91289467

1

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

add a comment |

1

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

+1. like this. Ruby has such great syntax. Love it.

– BuddyJoe
Sep 10 '09 at 20:40

meth = a.method? isn't this call the function already? what if the method returns something?

– user1735921
Nov 16 '15 at 7:07

FYI for when the method doesn't exist: "my_string".method('blah') #=> NameError: undefined method blah' for class String'

– Joshua Pinter
Dec 30 '17 at 22:31

add a comment |

Three Ways: `send` / `call` / `eval` - and their Benchmarks

Typical invocation (for reference):

s= "hi man"

s.length #=> 6

Using `send`

s.send(:length) #=> 6

Using `call`

method_object = s.method(:length) 

p method_object.call #=> 6

Using `eval`

eval "s.length" #=> 6

Benchmarks

require "benchmark" 

test = "hi man" 

m = test.method(:length) 

n = 100000 

Benchmark.bmbm {|x| 

  x.report("call") { n.times { m.call } } 

  x.report("send") { n.times { test.send(:length) } } 

  x.report("eval") { n.times { eval "test.length" } } 

}

...as you can see, instantiating a method object is the fastest dynamic way in calling a method, also notice how slow using eval is.

#######################################

#####   The results

#######################################

#Rehearsal ----------------------------------------

#call   0.050000   0.020000   0.070000 (  0.077915)

#send   0.080000   0.000000   0.080000 (  0.086071)

#eval   0.360000   0.040000   0.400000 (  0.405647)

#------------------------------- total: 0.550000sec



#          user     system      total        real

#call   0.050000   0.020000   0.070000 (  0.072041)

#send   0.070000   0.000000   0.070000 (  0.077674)

#eval   0.370000   0.020000   0.390000 (  0.399442)

Credit goes to this blog post which elaborates a bit more on the three methods and also shows how to check if the methods exist.

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

add a comment |

Three Ways: `send` / `call` / `eval` - and their Benchmarks

Typical invocation (for reference):

s= "hi man"

s.length #=> 6

Using `send`

s.send(:length) #=> 6

Using `call`

method_object = s.method(:length) 

p method_object.call #=> 6

Using `eval`

eval "s.length" #=> 6

Benchmarks

require "benchmark" 

test = "hi man" 

m = test.method(:length) 

n = 100000 

Benchmark.bmbm {|x| 

  x.report("call") { n.times { m.call } } 

  x.report("send") { n.times { test.send(:length) } } 

  x.report("eval") { n.times { eval "test.length" } } 

}

...as you can see, instantiating a method object is the fastest dynamic way in calling a method, also notice how slow using eval is.

#######################################

#####   The results

#######################################

#Rehearsal ----------------------------------------

#call   0.050000   0.020000   0.070000 (  0.077915)

#send   0.080000   0.000000   0.080000 (  0.086071)

#eval   0.360000   0.040000   0.400000 (  0.405647)

#------------------------------- total: 0.550000sec



#          user     system      total        real

#call   0.050000   0.020000   0.070000 (  0.072041)

#send   0.070000   0.000000   0.070000 (  0.077674)

#eval   0.370000   0.020000   0.390000 (  0.399442)

Credit goes to this blog post which elaborates a bit more on the three methods and also shows how to check if the methods exist.

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

add a comment |

Three Ways: `send` / `call` / `eval` - and their Benchmarks

Typical invocation (for reference):

s= "hi man"

s.length #=> 6

Using `send`

s.send(:length) #=> 6

Using `call`

method_object = s.method(:length) 

p method_object.call #=> 6

Using `eval`

eval "s.length" #=> 6

Benchmarks

require "benchmark" 

test = "hi man" 

m = test.method(:length) 

n = 100000 

Benchmark.bmbm {|x| 

  x.report("call") { n.times { m.call } } 

  x.report("send") { n.times { test.send(:length) } } 

  x.report("eval") { n.times { eval "test.length" } } 

}

...as you can see, instantiating a method object is the fastest dynamic way in calling a method, also notice how slow using eval is.

#######################################

#####   The results

#######################################

#Rehearsal ----------------------------------------

#call   0.050000   0.020000   0.070000 (  0.077915)

#send   0.080000   0.000000   0.080000 (  0.086071)

#eval   0.360000   0.040000   0.400000 (  0.405647)

#------------------------------- total: 0.550000sec



#          user     system      total        real

#call   0.050000   0.020000   0.070000 (  0.072041)

#send   0.070000   0.000000   0.070000 (  0.077674)

#eval   0.370000   0.020000   0.390000 (  0.399442)

Credit goes to this blog post which elaborates a bit more on the three methods and also shows how to check if the methods exist.

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

Three Ways: `send` / `call` / `eval` - and their Benchmarks

Typical invocation (for reference):

s= "hi man"

s.length #=> 6

Using `send`

s.send(:length) #=> 6

Using `call`

method_object = s.method(:length) 

p method_object.call #=> 6

Using `eval`

eval "s.length" #=> 6

Benchmarks

require "benchmark" 

test = "hi man" 

m = test.method(:length) 

n = 100000 

Benchmark.bmbm {|x| 

  x.report("call") { n.times { m.call } } 

  x.report("send") { n.times { test.send(:length) } } 

  x.report("eval") { n.times { eval "test.length" } } 

}

...as you can see, instantiating a method object is the fastest dynamic way in calling a method, also notice how slow using eval is.

#######################################

#####   The results

#######################################

#Rehearsal ----------------------------------------

#call   0.050000   0.020000   0.070000 (  0.077915)

#send   0.080000   0.000000   0.080000 (  0.086071)

#eval   0.360000   0.040000   0.400000 (  0.405647)

#------------------------------- total: 0.550000sec



#          user     system      total        real

#call   0.050000   0.020000   0.070000 (  0.072041)

#send   0.070000   0.000000   0.070000 (  0.077674)

#eval   0.370000   0.020000   0.390000 (  0.399442)

Credit goes to this blog post which elaborates a bit more on the three methods and also shows how to check if the methods exist.

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

answered Aug 8 '15 at 13:09

cwd

27.5k43141184

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

add a comment |

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

I was just finding this, and I noticed something that wasn't covered. What would I do if I wanted to do Class.send("classVariable") = 5? That throws an error. Is there any way around that? The same thing is true for using Class.method("classVariable").call() = 5

– thesecretmaster
Nov 20 '15 at 22:14

if you want to send some argument with send call use something like this ClassName.send("method_name", arg1, arg2)

– Aleem
Aug 30 '17 at 10:07

Shouldn't your benchmark for call include instantiating the method object (m.test.method(:length)) to accurately represent it's true time? When using call you're likely going to instantiate the method object every time.

– Joshua Pinter
Dec 30 '17 at 22:29

Blog post link is dead, btw.

– Joshua Pinter
Dec 30 '17 at 22:30

add a comment |

PS don't be lazy and actually type out your whole question, instead of linking to something.

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

add a comment |

PS don't be lazy and actually type out your whole question, instead of linking to something.

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

add a comment |

PS don't be lazy and actually type out your whole question, instead of linking to something.

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

PS don't be lazy and actually type out your whole question, instead of linking to something.

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

answered Sep 10 '09 at 20:16

dlamblin

27.1k1875109

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

add a comment |

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

Sorry. I'll copy some of the wording and translate to make it Ruby specific. +1

– BuddyJoe
Sep 10 '09 at 20:37

add a comment |

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