Updated: Simplified. 

#! perl -slw
use strict;

while( <DATA> ) {
    print "$1 : ", $2||$3 while m[
        (\w+)               ## the name
        \s+=\s+             ## the =
        (?:                 ## Either
            ' ( [^']+ ) '   ## all the non-quotes between quotes
        |                   ## or
            (.*?)           ## the minimum
        )
        \s{2,}              ## absorb the two or more spaces
    ]gx;
}

=results
P:\test>junk
drsubc : agauss(0, 1, 3)
delm1 : 0 + 0.045u*distm1
delm2 : 0 + 0.07u*distm2
delm3 : 0 + 0.07u*distm3
delm4 : 0 + 0.07u*distm4
delmt : 0 + 0.07u*distmt
delml : 0.16u + 0.43u*distml
delam : 0.32u + 0.86u*distam
dele1 : 0 + 0.25u*diste1
dele2 : 0 + 0.25u*diste2
delma : 0.16u + 0.6u*distma
pmsxt : npmsxt + 12.5u*dpmsxt
tih : 0.35u
capct : 0.50u + 0.13u*xdcapct
capcti : 0.55u + 0.13u*xdcapct
m1t : 0.41u + 0.05u*xdm1t
m1ti : 0.36u + 0.05u*xdm1t
m2t : 0.48u + 0.057u*dm2t
m3t : 0.48u + 0.057u*dm3t
m4t : 0.48u + 0.057u*dm4t
mtt : 0.48u + 0.057u*dmtt
qtt : 0.242u + 0.0202u*dqtt
htt : 0.242u + 0.0202u*dhtt
mlt : 2.0u + 0.2u*dmlt
amt : 4.0u + 0.4u*damt
e1t : 3.0u + 0.5u*de1t
e2t : 4.0u + 0.5u*xde1mat
mat : 4.0u + 0.4u*dmat
m1m2t : 0.35u + 0.05u*dm1m2t
=cut

__DATA__
drsubc  = agauss(0, 1, 3)   delm1   = '0 + 0.045u*distm1'             
+  delm2   = '0 + 0.07u*distm2'        delm3   = '0 + 0.07u*distm3'   
+             delm4   = '0 + 0.07u*distm4'                delmt   = '0
+ + 0.07u*distmt'                delml   = '0.16u + 0.43u*distml'     
+       delam   = '0.32u + 0.86u*distam'            dele1   = '0 + 0.2
+5u*diste1'                dele2   = '0 + 0.25u*diste2'               
+ delma   = '0.16u + 0.6u*distma'             pmsxt   = 'npmsxt + 12.5
+u*dpmsxt'           tih     = 0.35u                capct   = '0.50u +
+ 0.13u*xdcapct'           capcti  = '0.55u + 0.13u*xdcapct'          
+ m1t     = '0.41u + 0.05u*xdm1t'    m1ti    = '0.36u + 0.05u*xdm1t'  
+           m2t     = '0.48u + 0.057u*dm2t'             m3t     = '0.4
+8u + 0.057u*dm3t'             m4t     = '0.48u + 0.057u*dm4t'        
+     mtt     = '0.48u + 0.057u*dmtt'             qtt     = '0.242u + 
+0.0202u*dqtt'           htt     = '0.242u + 0.0202u*dhtt'           m
+lt     = '2.0u + 0.2u*dmlt'                amt     = '4.0u + 0.4u*dam
+t'                e1t     = '3.0u + 0.5u*de1t'            e2t     = '
+4.0u + 0.5u*xde1mat'             mat     = '4.0u + 0.4u*dmat'        
+        m1m2t   = '0.35u + 0.05u*dm1m2t'

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

In reply to Re: how to find what's not there with a regex? by BrowserUk
in thread how to find what's not there with a regex? by samizdat

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