Difference between revisions of "Hello world and hello Texas from Database"

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(editing for clarity)
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Install with something like Astronaut. Get to a GT.M prompt. Item 3 if you are using VistA Commander.
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Install VistA with something like Astronaut. Get to a Mumps prompt: choose item 3 if you are using VistA Commander.
 
   
 
   
 
MUMPS>write "hello world"
 
MUMPS>write "hello world"
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What the above hello TEXAS line does:
 
What the above hello TEXAS line does:
  
* Invoke the $piece command which is similar too but not exactly like the substring command in many other languages.
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* Invokes the $P[iece] command, which is similar to but not exactly like the substring command in many other languages.
* The ^ indicates that this is not a local variable, that it is looking for data on disk that others can see.
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* The ^ indicates that this is not a local variable; MUMPS will look for a [[Global~|global]] stored on disk and visible to other users.
* DIC indicates look in the data dictionary in file 5, field 48, item 0 with the ^ in this case being a delimiter and return only 1 token.
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* DIC's subscripts say to look in the data DICtionary in file 5, field 48, item 0, using the ^ in this case as a delimiter, and return the first piece.
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* Since ^DIC(5,48,0)="TEXAS^TX^48^^1^1", MUMPS writes "TEXAS".

Revision as of 18:25, 9 February 2010

Install VistA with something like Astronaut. Get to a Mumps prompt: choose item 3 if you are using VistA Commander.

MUMPS>write "hello world"

hello world

MUMPS>write "hello " write $P(^DIC(5,48,0),"^",1)

hello TEXAS

What the above hello TEXAS line does:

  • Invokes the $P[iece] command, which is similar to but not exactly like the substring command in many other languages.
  • The ^ indicates that this is not a local variable; MUMPS will look for a global stored on disk and visible to other users.
  • DIC's subscripts say to look in the data DICtionary in file 5, field 48, item 0, using the ^ in this case as a delimiter, and return the first piece.
  • Since ^DIC(5,48,0)="TEXAS^TX^48^^1^1", MUMPS writes "TEXAS".