
    dep.o: dep.src config1.cfg config2.cfg
        @echo the second preq is $(word 2,$^), the third is $(word 3,$^)



To implement a subscriptable object is easy, just implement `__getitem__` in this object&#39;s class definition.&lt;br/&gt;
But now I want to implement a subscriptable class. For example, I want to implement this code:

    class Fruit(object):
        Apple = 0
        Pear = 1
        Banana = 2
        #________________________________ 
        #/ Some other definitions,         \
        #\ make class &#39;Fruit&#39; subscriptable. /
        # -------------------------------- 
        #        \   ^__^
        #         \  (oo)\_______
        #            (__)\       )\/\
        #                ||----w |
        #                ||     ||

    print Fruit[&#39;Apple&#39;], Fruit[&#39;Banana&#39;]
    #Output: 0 2
I know `getattr` can do the same thing, but I feel subscript accessing is more elegant.

How to implement a subscriptable class in Python (subscriptable class, not subscriptable object)?

I&#39;m trying to get a list of all keys in a list of dictionaries in order to fill out the fieldnames argument for csv.DictWriter.

previously, I had something like this: 

    [
    {&quot;name&quot;: &quot;Tom&quot;, &quot;age&quot;: 10},
    {&quot;name&quot;: &quot;Mark&quot;, &quot;age&quot;: 5},
    {&quot;name&quot;: &quot;Pam&quot;, &quot;age&quot;: 7}
    ]

and I was using `fieldnames = list[0].keys()` to take the first dictionary in the list and extract its keys.

Now I have something like this where one of the dictionaries has more key:value pairs than the others (could be any of the results).  The new keys are added dynamically based on information coming from an API so they may or may not occur in each dictionary and I don&#39;t know in advance how many new keys there will be.


    [
    {&quot;name&quot;: &quot;Tom&quot;, &quot;age&quot;: 10},
    {&quot;name&quot;: &quot;Mark&quot;, &quot;age&quot;: 5, &quot;height&quot;:4},
    {&quot;name&quot;: &quot;Pam&quot;, &quot;age&quot;: 7}
    ]

I can&#39;t just use `fieldnames = list[1].keys()` since it isn&#39;t necessarily the second element that will have extra keys.

A simple solution would be to find the dictionary with the greatest number of keys and use it for the fieldnames, but that won&#39;t work if  you have an example like this: 

    [
    {&quot;name&quot;: &quot;Tom&quot;, &quot;age&quot;: 10},
    {&quot;name&quot;: &quot;Mark&quot;, &quot;age&quot;: 5, &quot;height&quot;:4},
    {&quot;name&quot;: &quot;Pam&quot;, &quot;age&quot;: 7, &quot;weight&quot;:90}
    ]
where both the second and third dictionary have 3 keys but the end result should really be the list `[&quot;name&quot;, &quot;age&quot;, &quot;height&quot;, &quot;weight&quot;]`




Extract all keys from a list of dictionaries

I need to get the nth dependency file from a rule, something similar to $n in bash. I need this because I&#39;d like to feed in individual dependency files as options to the build program.

Here&#39;s an example:

    dep.o: dep.src config1.cfg config2.cfg
        parse -cfg1 $2 -cfg2 $3 -o $@ $&lt;

Is it possible?

How to get the second dependency file using Automatic Variables in a Makefile?

I need to get the nth dependency file from a rule, something similar to $n in bash. I need this because I'd like to feed in individual dependency files as options to the build program.
Here's an example:
<pre><code class="hljs language-ruby">dep.o: dep.src config1.cfg config2.cfg
 parse -cfg1 $2 -cfg2 $3 -o $@ $&#x3C;
</code></pre>
Is it possible?

I&#39;m new to this. Just wanted to ask how to compile a makefile. I am using MinGW compiler in C language. Do I have to save all my files in MinGW\bin? because right now my files are in a different directory.

Appreciate the help.

How to compile makefile using MinGW?

I want to print some message while doing build process with a `makefile`. The following one can print the message, but it will not execute the script after it.  How can I fix this issues? 



    ifeq (yes, ${TEST})
            CXXFLAGS := ${CXXFLAGS} -DDESKTOP_TEST
    test:
            @echo &#39;************  TEST VERSION ************&#39;
    else
    release:
            @echo &quot;************ RELEASE VERSIOIN **********&quot;
    endif







How can I print message in Makefile?

I know that the `@` prefix suppresses output from a shell command in Makefiles, and also that the `-` prefix will ignore errors from a shell command. Is there a way to combine the two, i.e. a prefix that suppresses output and ignores errors? I don&#39;t think `@-` or `-@` works.

Suppress and ignore output for Makefile?

I have a makefile in a directory of mine which builds scripts with certain environment variables set. What if I want to create another makefile in the same directory with different environment variables set? How should I name the two make files? Does `makefile.1` and `makefile.2` work? How do I call them?


multiple makefiles in one directory

In a GNU makefile, I am wondering if it is possible, with an file list input, to make a file list output with new extensions.

In input, I get this list:

    FILES_IN=file1.doc file2.xls

And I would like to build this variable in my makefile from **FILES_IN** variable:

    FILES_OUT=file1.docx file2.xlsx

Is it possible ? How ?

It&#39;s quite difficult because I have to parse file list, and detect each extension (.doc, .xls) to replace it to correct extension.




How to change the extension of each file in a list with multiple extensions in GNU make?

I installed MinGW and MSYS, added `C:\MinGW\bin` to `PATH` but I still can&#39;t run Makefile on Windows&#39; `cmd`. I would like to run cmd.exe and there type, for example, `make all` but my cmd says that there is no such command. 

What should I do? I don&#39;t want to use MSYS shell, that&#39;s not the point. Any ideas how to use GNU Make in Windows cmd as I can do it in Ubuntu? I&#39;m not interested in `Cygwin`.

How to use GNU Make on Windows?

&gt; **Possible Duplicate:**  
&gt; [Make error: missing separator](https://stackoverflow.com/questions/920413/make-error-missing-separator)  

&lt;!-- End of automatically inserted text --&gt;

Have this code in makefile:

    PROG = semsearch
    all: $(PROG)
    %: %.c
    gcc -o $@ $&lt; -lpthread
    
    clean:
    rm $(PROG)

and the error

    missing separator. stop.

Can someone help me?

Makefile - missing separator

One rule in my Makefile zips an entire directory (`res/`) into a ZIP file. Obviously, this rule needs to execute when *any* file under the `res/` directory changes. Thus, I want the rule to have as a prerequisite all files underneath that directory. How can I implement this rule?

In Bash [with the `globstar` option enabled](https://unix.stackexchange.com/questions/49913/recursive-glob/49917#49917), you can obtain a list of all the files in that directory using the wildcard pattern `res/**/*`. However, it doesn&#39;t seem to work if you specify it as a prerequisite in the Makefile:

    filename.jar: res/**/*

Even after `touch`ing a file in `res/`, Make still reports

    make: `filename.jar&#39; is up to date.

so clearly it is not recognizing the pattern.

If I declare the directory itself as a prerequisite:

    filename.jar: res

then Make will not re-execute when a file is modified (I think `make` only looks at the modified date of the directory itself, which only changes when immediate children are added, removed, or renamed).

Content Type	Original Author	Original Content on Stackoverflow
Question	Yu Zhou	View Question on Stackoverflow
Solution 1 - Makefile	Beta	View Answer on Stackoverflow

How to get the second dependency file using Automatic Variables in a Makefile?

Makefile Problem Overview

Makefile Solutions

Solution 1 - Makefile

Extract all keys from a list of dictionaries

How to implement a subscriptable class in Python (subscriptable class, not subscriptable object)?

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