TeamCity parameter style usage in GitLab

Working on converting from TeamCity to GitLab for our CI/CD process. Is there a way to duplicate the functionality used in TeamCity templates?

Example 1:

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variables:
new_var1: this
new_var2: is
new_var3: a
new_var4: sentence
new_var5: {new_var1}{new_var2}{new_var3}{new_var4}

echo ${new_var5} = thisisasentence

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variables:
new_var4: line

echo ${new_var5}=thisisasentence

In this case, I would expect thisisaline

I found this is a work around, but not ideal:

Example 2:

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variables:
new_var1: this
new_var2: is
new_var3: a
new_var4: sentence
new_var5: {new_var1}{new_var2}{new_var3}{new_var4}

echo ${new_var5} = thisisasentence

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variables:
new_var6: line
new_var7: {new_var1}{new_var2}{new_var3}{new_var6}

echo ${new_var6}=thisisaline